COM Surrogate in Windows 10 (dllhost.exe) – Why Microsoft Invented

com surrogate

Thousands of us must be using a personal computer for years now. Still, we do not know about a lot of features and software present in our PCs. Moreover, when you open your Windows Task Manager, you see a lot of entries. Knowing all of them is not possible if you are an expert and not a novice like me. One such entry is COM surrogate, also known as dllhost.exe.

Hearing the name for the first time, aren’t you? Well, do not worry as we have got you covered. In today’s article, we will talk about everything about the dllhost.exe COM surrogate. 

The simple explanation for COM surrogate is that it is a Microsoft-designed program that creates the present images’ thumbnails. Moreover, it also provides a quick preview of all the images when highlighted. The Component Object Model or COM processes photos, videos, and other media files for generating thumbnails. 

Now, a lot of people assume that this program is a virus. No, it is not a virus and not even close to that. It is an in-built program creating thumbnails of your documents, images, videos, and other file types. Therefore, to clear the concept of this program, scroll down, and learn more. 

Read: How To Fix Can’t Login to AOL Login Mail Issues – A Detailed Guide

What is a COM surrogate?

As mentioned earlier, COM denotes Component Object Model. Microsoft introduced this program back in 1993. This allows developers and programmers to create “COM objects” by using a myriad of programming languages. Moreover, these COM objects get access to other applications and further extend them.

For instance, the Windows Task Manager uses COM objects to create thumbnail files or images when it opens a folder. The COM object handles the processing of images, files, videos, and documents to generate thumbnails. Hence, this allows File Explorer to extend with support for new image codecs, video codecs, etc. 

However, as useful as it sounds, it can create problems as well. If a COM object crashes, then it will likely take down the host process. At a certain point, it was very common for COM to crash. Hence, taking down Windows Explorer. 

Therefore, to fix this issue, Microsoft created a COM surrogate. So, if you have been wondering, what is a COM surrogate? Then, let us tell you. COM surrogate is successfully run the COM object outside the actual process that requested it. Now, if the COM object crashes, it will take down the COM surrogate and not the original host. Hence, the original host won’t crash. 

For instance, the File Explorer for generating thumbnails starts the COM surrogate. Now, the COM surrogate will host the COM object. The COM object then does the work. If somehow the COM object crashes, it will take the COM surrogate and not File Explorer. Therefore, minimizing casualties.

In other words, COM surrogate asks COM objects to host in some different process which Surrogate cannot do. So, in that way, if it crashes which processing, the COM surrogate will go down or sacrifice itself. The File Explorer or the Windows Explorer will be completely safe and secured. 

What is this sacrifice?

You have read the word “sacrifice” above. But what is this sacrifice? For knowing this, let’s consider an example and read it below.

The most common use of COM surrogate is Windows Explorer creating and building thumbnails. In older versions, the File Explorer would generate thumbnails under itself. So, this often resulted in crashing. This was because the thumbnail extractors are not always reliable.

If you have been using Windows for quite a few years, then you would have seen this once or maybe multiple times that File Explorer crashed whenever you opened a folder with hundreds of images or file documents.  So, this was natural earlier.

But now, whenever File Explorer or Windows Explorer think that a crash might occur, it creates a COM surrogate. The COM surrogate handles the problematic aspect of this process. So, now when you open a folder with lots of images and lots of thumbnails that need to be created, File Explorer shifts this task politely to COM surrogate. So, while loading the thumbnails, the File Explorer does not go down if the process crashes. 

Why did Microsoft create a COM surrogate?

COM objects were not perfect at all. They were the sole reasons why Windows Explorer processes would go down again and again. Due to this, a lot of Windows administrators and users were facing frequent crashes. They had only one option left, which was to restart their system.

Microsoft created a COM surrogate for preventing the ship from sinking. And, that is what it does for Windows Operating System. COM is available on Windows 10, and Microsoft is in no hurry to replace it. Gradually over the years, it has become the backbone of the service. Therefore, COM surrogate saves you from frequent crashes and restarts. 

Is COM surrogate a virus?

Now, let’s answer the most popular and in-demand question regarding COM surrogate. It is not a virus, but individual cybercriminals can use its name for malicious processes on your system. As a result, you may find that the COM surrogate is causing duplicates and High CPU in the Task Manager. 

So, one of the quickest ways to check if you are being fooled and trapped by a cybercriminal or not is by detecting the file location. You must check the dllhost.exe file location. Hence, to do this, follow the steps below:

  1. Press “Ctrl + Alt + Delete” to open the Windows Task Manager. Then, simply click on Task Manager.
  2. To search for COM surrogate easily and quickly, keep on pressing the “C” button repeatedly. By pressing the first alphabet key, you can effortlessly search for any file, folder, or document. 
  3. After you have found it, then right-click on it to check the file location. If you see a lot of dllhost.exe running, then you have to repeat the process for each one of them.
  4. Now, you have to check whether the file belongs to either C:/winnt/system32 or C:/Windows\System32. If your file is located in any one of these locations, you are dealing with an original COM surrogate. If the file is located anywhere other than these two locations, you are dealing with a virus. 

Another way to check that you have no malicious software or virus in your system is by booting your PC in safe mode and then running your antivirus software. The program or software will either use a machine-learning or signature-based model to detect whether or not the COM surrogate is a virus.

Some Viruses using the name

Some viruses’ examples using this process are Artemis, Poweliks, Loveleet, Nashi. A, and possibly Trojans/rootkits. Therefore, the original COM surrogate is not a virus, but viruses might use its name to disrupt your computer. 

Hence, follow the above tricks and stay attentive. 

Should you disable COM surrogate?

You cannot, and you must disable dllhost.exe. It is an essential part of the Windows OS. Your File Explorer mustn’t crash and also COM objects to operate smoothly to be to the point. The processes can be used by a myriad of programs for completing specific tasks outside the host. 

If dllhost.exe is bothering you, then you can simply restart your computer. If it annoys you quite frequently, you must take a more in-depth look into it by running a virus scan. But, it is always recommended that you should never disable the COM surrogate. 

How to Check Which Process Started DLLHOST.EXE?

The Task Manager does not allow you to see the detailed description of the dllhost.exe processes. Now you might find multiple copies of the program running and wonder which programs started them. So, to check which program started it, you need to download Process Explorer. Process Explorer, the best Task Manager alternative.

Process Explorer gives you detailed information about what is going on and taking place in your system. Moreover, it also explains which program started the dllhost.exe process. So, do know about which program started it, you have to look through the dllhost.exe process first. Then, on the Description field, you will find COM surrogate. When you move your mouse over it, you will find the description of what started it. 

Now, if you are unable to find dllhost, then simply press “Ctrl + F.” This will open the search box. Next, simply enter dllhost.exe and check what programs are using it. If you do not find any, then it means that no plan is currently using COM surrogate. 

Therefore, by following this process and download Process Explorer, you can easily find which program is giving rise to dllhost.exe. There are other Task Manager alternatives, as well. You can download any of them and check. But, the best option is Process Explorer.

If you are curious about the program giving rise to COM surrogate, follow the method above. 

What are the common COM Surrogate Issues?

Listed below are some of the most common COM surrogate issues. Though dllhost.exe is real and legitimate, it can give a headache to Windows users. So, let’s check out the common problems and get insight. 

High CPU

Many PC users have found high RAM usage. Dllhost.exe has a high RAM usage. Now, this process causes high CPU during outdated codecs, corrupted files, and malware attacks. So, it is recommended that you should not ignore this issue and take immediate action. Below we have mentioned all the solutions by which you can solve this problem and other dllhost.exe problems. 

COM Surrogate has Stopped Working

This problem generally occurs when you are browsing media files such as images and videos stored in your system. The issues giving rise to this problem are false positive antivirus interruption, disk errors, and outdated drivers. So, if your COM surrogate is causing the problem, then you must check for this issue. 

Dllhost.exe Popping Up

Another issue that people have addressed in different forums is that dllhost.exe keeps on popping up. Now, a lot of people get annoyed with these repeated pop-ups. Now, when COM surrogate pop-ups on your screen, this either minimizes or disappears the other program for you. It happens every five to ten minutes. Hence, you can just assume how annoying it is to deal with it. To solve this issue, you can try updating codecs, or you can even check for disk errors. 

Dllhost.exe Asking for Password

Some users have also reported the issue of COM surrogate asking for a password for the email. Now, this can happen if you shut down the process manually. So, the first solution to this is by booting up your system. So, after doing this, just check once if you are getting the prompts or not. 

If you are not getting the issue in the Safe mode, then that means it was related to some third-party application. Other reasons contributing to such a problem are incorrect software installation, outdated system version, or some other issue. 

Other Com Surrogate Issues are

  1. Dllhost.exe has frozen or not responding.
  2. It keeps on crashing.
  3. It has stopped working.
  4. Dllhost.exe taking memory.

Hence, these were some of the issues that you may face with the COM surrogate. A lot of people are annoyed by these problems, and they cannot even disable this program. It is not at all advised that you should disable Dllhost.exe. So, the best thing you can do is finding solutions to the problems.

In our next section, we have mentioned and explained all the problems discussed above. Yes, we have got you covered. We have provided all the steps by which you can solve the COM surrogate problems. 

So, scroll down and check all the solutions and get rid of the COM surrogate problems. Read the methods correctly and apply them wisely.

Methods to Fix the COM Surrogate Problems

We have discussed as well as mentioned a number of COM surrogate problems. But, the most common problem is COM surrogate has stopped working. So, we have discussed specific methods to solve this issue. If you face any of the above issues, then the below-mentioned methods are ideal for them. So, let’s check out the methods to fix this problem. 

Update Codecs

So, the first and one of the easiest methods to solve the problems mentioned above. Hence, you can update Windows 7, 8, or 10’s codecs. Therefore, updating the codec can be the most useful method. You can update codecs lucidly. So, you can download as well as install Windows Codec from the below-mentioned links:

Link to Windows 7 Codec Pack:    

Link to Windows 10 and 8 Codec Pack: 

Hence, installing codecs can solve the issues. After you install and update the codecs, you will find that your COM surrogate has started working. If it stills fails to work, then you can check out the other methods. 

Reset Internet Explorer

Another method for your COM surrogate to work is by resetting your Internet Explorer. The issue can be due to the corruption of cached files. So, in such an instance, it is best if you reset your Internet Explorer. To reset IE, follow the steps:

  1. Press and hold the “Windows key” and then press “R.” When the dialog will appear, type inetcpl. cpl and then click on “OK.” 
  2. Next, all you have to do is move to the “Advanced Tab” and then select “Reset.” 
  3. Lastly, select “Delete Personal Settings.” Then you have to hit the “Reset” button again. After you have done the procedure, reboot your system. Then, test it. 

Check Your Disk for Errors

If the COM surrogate error occurs while you were opening a drive except for the C drive, this could be due to a drive error. If you do not have any additional drives, you must look into your C drive. So, to check the issue, go through the following steps:

  1. Hold the Windows key on your keypad, and then press E. If you have Windows Vista or Windows 7, then you will find the drives listed.
  2. If you have Windows 8 or Windows 10, choose “This PC” from the left-hand side. Then, right-click on the drive you wish to check. Then, select “Properties.”
  3. On top, you will find the “Tools” tab. Then, under “Error-checking,” select “Check Now.” You have to check both the options and then simply click on “Start.” 

Therefore, if you follow the above steps, you can quickly check if your Drive is causing the COM surrogate problems. 

DLLs Re-register

You have to run the following commands in the command prompt.

  • Click on “Start” and then type “cmd.” Next, you have to right-click on cmd and select “Run as Administrator.”
  • Now, the Command Prompt will appear on your screen. Type the following commands and then select “Enter.”


regsvr32 vbscript.dll 

So, by typing the above commands and selecting “Enter,” If this method did not solve the problem, try out the following ones. 

Roll Back Driver

  1. Firstly, hold the Windows key and then tap on R. When the Run dialog appears, type “hdwwiz.cpl” and select OK.
  2. Now, in the Device Manager, scroll to the “Display Adapters.” Then, right-click and select “Properties.”
  3. Lastly, click on the “Roll Back Driver” and then follow the on-screen instructions.

So, follow the on-screen instructions and complete the process. After completing the process, the issue will be solved. 

Add Dllhost.exe to the DEP Exception

First, select Start and then navigate to Control panel, then System. Then, select “Advanced System Settings,” click on “Performance Settings.” Next, tap on Data Execution Prevention or DEP. 

  1. Now you have to select Turn on DEP for all programs and services except those I select:
  2. Next, tap on “Add.” If you have a 32-bit Windows machine, then navigate to C:\Windows\System32\dllhost.exe, and to C:\Windows\SysWOW64\dllhost.exe on 64-bit Windows Machine. 
  3. Lastly, you have to add dllhost.exe to exception, and then click on “Apply Changes” and then “OK.”

Switch to either Disable Thumbnails/ Details View or List

We have mentioned earlier that dllhost.exe is responsible for the thumbnails. If you want to avoid problems with the thumbnails, you can simply disable the thumbnails. 

Or, you can even switch to Details View to List:

  1. Open File Explorer.
  2. Then, select “View Tab” and then choose either List or Details view option. 

Hence, by following the steps, you can disable the thumbnails or switch to List. You can do either or. It is totally at your discretion. 

Delete Thumbnails

You can even delete thumbnails to fix the problem. You can remove the thumbnails by using the Disk Cleanup Tool. Now, this will pressurize the Windows for building Thumbnails cache. After deleting thumbnails, hopefully, your COM surrogate problems will get solved. 

Update your System’s Antivirus

Another method you can apply to fix the COM surrogate problem is by updating your Antivirus. Old Antivirus versions can cause issues as well. It has been noted that Kaspersky Antivirus can cause dllhost.exe problems.

So, if none of the methods are working for you, then try out this method. Update your antivirus, and the problem will disappear as well. 

Hence, these were the various methods you can try out to solve the dllhost.exe problems. We are sure that any one of the above methods will surely help you in solving the problem. 


Q.1. Is COM Surrogate a virus?

Ans- No. COM Surrogate is not a virus. It is a Microsoft-built program. But, be aware that viruses can disguise themselves in the program’s name and attack your system.

Q.2. Should I remove the COM Surrogate?

Ans- No. You cannot disable or remove the dllhost.exe. It is an in-built Windows part. It enables the COM object to works seamlessly without crashing and taking down File Explorer. So, it is advisable not to remove the program.


We have covered everything related to COM surrogate. I hope you have learned and come to know about the program entirely. If you are facing any problem with the dllhost.exe program, you can trust us and try out the methods. 


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