Oct 05, 2016 I am running Windows 10 Pro Insider Preview 11082 on my Surface Pro 3 and within the past week to two weeks I am getting a pop window from 'Windows Security' that says just COM Surrogate. The pop-up is wanting me to log into my work email address or Microsoft account email address. If I close it without logging in or actually do log into either account the window will reappear. Dec 11, 2017 How to Troubleshoot COM Surrogate Issues in Windows 10. Ben Stegner December 11, 2017 6 minutes. How to Master the Command Prompt in Windows 10 How to Master the Command Prompt in Windows 10 This article makes the Windows 10 Command Prompt approachable and way more useful. Learn how to run multiple commands, get help on any. Jan 15, 2018 COM Surrogate is a basic Windows 10 process that is in charge of showing thumbnails and similar information. Although this is a basic process, some users have reported issues with it, so let’s fix those issues. Before we start fixing issues with COM Surrogate, make sure that your Windows 10.
If you poke around in your Task Manager, there’s a good chance you’ll see one or more “COM Surrogate” processes running on a Windows PC. These processes have the file name “dllhost.exe”, and are part of the Windows operating system. You’ll see them on Windows 10, Windows 8, Windows 7, and even earlier versions of Windows.
RELATED:What Is This Process and Why Is It Running on My PC?
This article is part of our ongoing series explaining various processes found in Task Manager, like Runtime Broker, svchost.exe, dwm.exe, ctfmon.exe, rundll32.exe, Adobe_Updater.exe, and many others. Don’t know what those services are? Better start reading!
What Is COM Surrogate (dllhost.exe)?
COM stands for Component Object Model. This is an interface Microsoft introduced back in 1993 that allows developers to create “COM objects” using a variety of different programming languages. Essentially, these COM objects plug into other applications and extend them.
For example, the Windows file manager uses COM objects to create thumbnail images of images and other files when it opens a folder. The COM object handles processing images, videos, and other files to generate the thumbnails. This allows File Explorer to be extended with support for new video codecs, for example.
However, this can lead to problems. If a COM object crashes, it will take down its host process. At one point, it was common for these thumbnail-generating COM objects to crash and take down the entire Windows Explorer process with them.
To fix this sort of problem, Microsoft created the COM Surrogate process. The COM Surrogate process runs a COM object outside the original process that requested it. If the COM object crashes, it will only take down the COM Surrogate process and the original host process won’t crash. For example, Windows Explorer (now known as File Explorer) starts a COM Surrogate process whenever it needs to generate thumbnail images. The COM Surrogate process hosts the COM object which does the work. If the COM object crashes, only the COM Surrogate crashes and the original File Explorer process will keep on trucking.
“In other words”, as official Microsoft blog The Old New Thing puts it, “the COM Surrogate is the I don’t feel good about this code, so I’m going to ask COM to host it in another process. That way, if it crashes, it’s the COM Surrogate sacrificial process that crashes instead of me process.”
And, as you might have guessed, COM Surrogate is named “dllhost.exe” because the COM objects it hosts are .dll files.
How Can I Tell Which COM Object a COM Surrogate Is Hosting?
The standard Windows Task Manager doesn’t give you any more information about which COM object or DLL file a COM Surrogate process is hosting. If you want to see this information, we recommend Microsoft’s Process Explorer tool. Download it and you can just mouse-over a dllhost.exe process in Process Explorer to see which COM Object or DLL file it’s hosting.
As we can see in the screenshot below, this particular dllhost.exe process is hosting the CortanaMapiHelper.dll object.
Can I Disable It?
You can’t disable the COM Surrogate process, as it’s a necessary part of Windows. It’s really just a container process that’s used to run COM objects that other processes want to run. For example, Windows Explorer (or File Explorer) regularly creates a COM Surrogate process to generate thumbnails when you open a folder. Other programs you use may also create their own COM Surrogate processes. All the dllhost.exe processes on your system were started by another program to do something that program wants done.
Is It a Virus?
The COM Surrogate process itself is not a virus, and is a normal part of Windows. However, it can be used by malware. For example, the Trojan.Poweliks malware uses dllhost.exe processes to do its dirty work. If you see a large number of dllhost.exe processes running and they’re using a noticeable amount of CPU, that could indicate the COM Surrogate process is being abused by a virus or other malicious application.
RELATED:What’s the Best Antivirus for Windows 10? (Is Windows Defender Good Enough?)
If you’re concerned that malware is abusing the dllhost.exe or COM Surrogate process, you should run a scan with your preferred antivirus program to find and remove any malware present on your system. If your antivirus program of choice says everything is fine but you’re suspicious, run a scan with another antivirus tool to get a second opinion.
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Have you ever opened up the Windows Task Manager and wondered what half of the entries areHow to Handle Suspicious Windows Task Manager ProcessesHow to Handle Suspicious Windows Task Manager ProcessesCTRL + ALT + DEL aka three-finger salute is the quickest way to add to your confusion. Sorting through Task Manager Processes, you may notice something like svchost.exe using 99% of your CPU. So now...Read More? While newer versions of Windows have friendlier namesHow Windows Has Become More User-Friendly, 5 ExamplesHow Windows Has Become More User-Friendly, 5 ExamplesOver time, Windows has smoothed rough edges and created a more user-friendly experience, especially for novice users. Here are five big reasons that Windows is easier to use than ever before.Read More for most processes, finding out exactly what they do is tough.
One process you might have seen is COM Surrogate, also called dllhost.exe. What is this process for, why does it run, and does it mean you have a virus? Read on to find out.
What Is COM Surrogate?
According to Microsoft, COM Surrogate “is a fancy name for [s]acrificial process for a COM object that is run outside of the process that requested it.” That’s not clear at all, so let’s break that definition down and look at a few examples.
First, a COM (which stands for Component Object Model) object is essentially a Microsoft-designed standard for software created so that processes can easily talk to each other. For example, say you have an Excel spreadsheet embedded in a Word document8 Surprising Ways You Can Import Data into Microsoft Word8 Surprising Ways You Can Import Data into Microsoft WordKnowing how to import data into Microsoft Word from any source, including Excel, PDF files, or other Word documents, can save you a lot of time. We'll show you all the tricks.Read More. Seeing the changes you make in Excel automatically update the Word spreadsheet is possible thanks to these shared objects.
These COM objects, as is evident from the process name, are really DLL files. These reside in protected Windows folders5 Default Windows Files and Folders You Should Never Touch5 Default Windows Files and Folders You Should Never TouchWindows contains countless default files and folders, many of which the average user shouldn't touch. Here are five folders you should leave alone to avoid damaging your system.Read More and let the operating system (OS) function as it’s supposed to.
What’s the Sacrifice?
Next, we should examine what “sacrificial process” means. For that, we turn to another example.
A common use for COM Surrogate is the File Explorer building thumbnails. In older versions of Windows, the Explorer process would try to generate thumbnails under itself. This often resulted in crashes because thumbnail extractors aren’t always reliable.
You may have seen this behavior yourself: opening a folder with hundreds of images or a file type that Windows didn’t expect would sometimes cause Explorer to crash in the old days.
So, whenever File Explorer thinks that a crash may soon occur, it creates a COM Surrogate process to handle the risky behavior. In this case, when you open a folder that has a lot of thumbnails to generate, File Explorer passes the job off to COM Surrogate. That way, if the thumbnail loading crashes, the Explorer process doesn’t go down with it.
Can I Kill This Process?
Unlike some other important Windows processes7 Windows Task Manager Processes You Should Never Kill7 Windows Task Manager Processes You Should Never KillSome Windows processes can freeze or crash your system if terminated. We'll show you which Task Manager processes you should leave alone.Read More, you can open the Task Manager (Ctrl + Shift + Esc) and kill any COM Surrogate processes you see. However, doing so usually isn’t a good idea. Programs create these processes whenever they need them to perform some action, so killing them will stop whatever they’re working on.
You can’t disable COM Surrogate, as it only runs when another program requests it.
How Do I See Which Process Started It?
Com Surrogate Windows 10 Start Menu
The Task Manager, basic as it is, doesn’t let you see detailed info about COM Surrogate processes. Since you’ll often see multiple copies of it running, you might wonder which programs started them. For that, you’ll need to download Process Explorer, one of the best Task Manager alternatives5 Powerful Alternatives to the Windows Task Manager5 Powerful Alternatives to the Windows Task ManagerTask Killer would be a better name for the native Windows Task Manager since we only bring it up to kill unresponsive processes. Alternative Task Managers allow you to actually manage your processes.Read More.
Process Explorer gives loads of details about what’s running on your computer, and it can tell you what process started a COM Surrogate. Look through the list for a dllhost.exe process — they have COM Surrogate in the Description field. Mouse over it, and you’ll see some info about what’s responsible for it.
If you can’t find any dllhost processes, press Ctrl + F to open the search bar. Enter dllhost.exe to easily find all instances of it. If you don’t see any, it’s possible that no programs are using COM Surrogates at the moment.
In the below example, we’ve found that this COM Surrogate is handling thumbnails.
How Can I Fix a COM Surrogate Crash?
You likely haven’t ever noticed COM Surrogate unless you’ve seen an error that lets you know it stopped working and affects your Windows 10 performance14 Ways to Make Windows 10 Faster and Improve Performance14 Ways to Make Windows 10 Faster and Improve PerformanceIt's not hard to make Windows 10 faster. Here are several methods to improve the speed and performance of Windows 10.Read More. Most of the time, a particular file will cause this error, usually related to thumbnails. If you see COM Surrogate errors regularly, here are a few solutions you can try:
- Update/uninstall any codec packs and media software. If you use software like the K-Lite codec pack, or media tools such as DivX or Nero, something with them could cause this problem. Consider uninstalling them, as you really don’t need these codec packs anymoreHow to Troubleshoot Video & Audio Playback Issues on Your Windows PCHow to Troubleshoot Video & Audio Playback Issues on Your Windows PCNo video, no sound, how frustrating! Luckily your problem is likely to be a common Windows issue that we can help you troubleshoot right here, right now.Read More since VLC plays everything, and Nero has plenty of free alternativesThe Best, Free Alternatives to Nero CD/DVD BurnerThe Best, Free Alternatives to Nero CD/DVD BurnerDon't waste money on a CD/DVD burning tool! A freeware application might be all you need. Here we have compiled five alternatives to Nero Burning ROM for your Windows PC.Read More.
- Install Windows Updates. Some people have reported that installing the latest updates solves this issueHow & Why You Need To Install That Security PatchHow & Why You Need To Install That Security PatchRead More. It’s not always the solution, but it’s an easy first step. Perhaps there’s some small hiccup with a particular file type that Microsoft fixed with the latest patches.
- Delete existing thumbnails. If a corrupted thumbnail is causing COM Surrogate to crash, you can remove it using the Disk Cleanup tool7 Hidden Windows Caches & How to Clear Them7 Hidden Windows Caches & How to Clear ThemCached files can take up a lot of bytes. While dedicated tools can help you free up disk space, they might not clear it all. We show you how to manually release storage space.Read More. This will force Windows to rebuild the thumbnail cache, which could clear up the problem.
- Identify the problematic file. Use the Process Explorer, as discussed above, to see what file dllhost is trying to access. If it points to a specific file, that’s almost certainly your problem. Delete that file and see if the problems subside.
- Remove COM Surrogate from the Data Execution Prevention list. Windows uses something called Data Execution Prevention (DEP) to prevent malicious code from running on your system. You can exclude certain processes from this list, and doing so for COM Surrogate could stop the error.
- Type advanced system into the Start Menu and select View advanced system settings. Click the Settings button under the Performance tab, then select the Data Execution Prevention tab.
- Choose the second option, Turn on DEP for all programs… and click the Add button.
- Browse to C:WindowsSystem32dllhost.exe on a 32-bit system, or C:WindowsSysWOW64dllhost.exe on 64-bit Windows. Click OK to save your changes.
- Scan your hard drive for problems. If this problem occurs with no patterns, you should run a few scans on your computer. At the Command prompt, use the SFC commandHow to Fix Corrupted Windows System Files With One CommandHow to Fix Corrupted Windows System Files With One CommandIf you're seeing weird issues in Windows, it could be due to system files becoming corrupted. Here's how to fix them using the System File Checker.Read More to repair Windows files and the CHKDSK commandIs CHKDSK Stuck? Fixes for When Check Disk Won't WorkIs CHKDSK Stuck? Fixes for When Check Disk Won't WorkCHKDSK can seriously deflate your Windows boot time. More importantly, it indicates that something's not right. Here's what Check Disk does and how you can use it.Read More to check for hard drive errors.
- Re-register a few DLL files in the Command Prompt.In the Command PromptHow to Master the Command Prompt in Windows 10How to Master the Command Prompt in Windows 10This article makes the Windows 10 Command Prompt approachable and way more useful. Learn how to run multiple commands, get help on any command, and more.Read More, running the commands regsvr32 vbscript.dll and regsvr32 jscript.dll will re-register two DLLs that could fix the COM Surrogate crash.
- Check your antivirus. Some have reported that Kaspersky antivirus conflicts can cause this issue. Try disabling antivirus protection and see if accessing that file/folder still results in an error.
- If you don’t use them, you can disable thumbnails completelyWhy You Should Disable Thumbnails in WindowsWhy You Should Disable Thumbnails in WindowsYou're probably used to Windows thumbnails, but did you know that you don't really need them? In fact, there are several benefits to turning them off.Read More.
Can This Signify a Virus?
The normal COM Surrogate process is a normal part of Windows and isn’t malicious. However, some malware has been known to use dllhost processes for nefarious purposes. Seeing a large number of COM Surrogate entries in the Task Manager using a lot of the CPUHow to Fix High CPU Usage in WindowsHow to Fix High CPU Usage in WindowsDoes your PC suffer from high CPU usage up to 100%? Here's how to fix high CPU usage in Windows 10.Read More is a sign that you could have an infection.
Because this type of malware mimics important system processes and files, we don’t recommend trying to remove it on your own. You might end up deleting a critical file by mistake. Instead, run a scan with your installed antivirusThe 8 Best Security Software for Windows 10 Malware ProtectionThe 8 Best Security Software for Windows 10 Malware ProtectionWant to tighten security on your PC? It's a good idea, so take a look at these fantastic antivirus choices for Windows 10.Read More and then try a second one to make sure you’re clean.
Consult our list of the best nag-free antivirus programsTop Free Antivirus Apps Without Nag Screens and BloatwareTop Free Antivirus Apps Without Nag Screens and BloatwareNagging antivirus apps are a huge pain. You don't have to put up with them, even for free. Here are the best antivirus programs that don't come with popups or bundled junk.Read More if you need a recommendation. Don’t forget that you can run a scan with Windows Defender even if you don’t use it all the time (though you probably should4 Reasons to Use Windows Defender in Windows 104 Reasons to Use Windows Defender in Windows 10In the past, Windows Defender was overshadowed by other options, but now it's quite a contender. Here are a few reasons why you should consider dropping your security suite in favor of Windows Defender.Read More).
Type defender into the Start Menu and open Windows Defender Security Center. Select Virus & threat protection, then click the Quick scan button to run a scan.
No matter which antivirus you use, getting a second opinion from the venerable Malwarebytes is smart too.
That’s All for COM Surrogate
We’ve covered everything you should know about the COM Surrogate process. As it turns out, this process is a helper that another program can create when it wants to outsource some task. Because of this, you’ll see various numbers of COM Surrogate running at different times. You know what to do to troubleshoot crashes, and what to look for to detect a virus.
For more Windows knowledge, check out our newcomer’s guide to PC troubleshootingWindows Troubleshooting for DummiesWindows Troubleshooting for DummiesWindows takes a lot of crap for problems outside of its control. Learn about the biggest issues people incorrectly pin on Windows and how to actually troubleshoot them.Read More.
Have you ever noticed the COM Surrogate process running on your PC? Has it had issues with crashing, and what fixed it for you? Share with us in the comments!
File Open In Com Surrogate
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Com Surrogate Windows 10 High Cpu
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