Vista, XviD and the COM Surrogate

October 23, 2007

Vista busy cursor I thought things were going too smoothly with Vista. Should have known.

This time I made the cardinal error of installing the XviD codec so I could compress some video taken on my travels for upload to YouTube. A new error message started to appear:

“The COM Surrogate has stopped working”

Huh? What the hell is the COM Surrogate, thought I? Well, it turns out this is the new Vista name for the dll host service (dllhost.exe). This is the dummy process that acts as a host to “unattached” dlls, dynamic link libraries that are normally called by applications to do common tasks for them. Sometimes these dlls are required to run “on their own”, rather than being loaded up by a specific program, and Windows provides a host process, dllhost.exe, to load them up and run them.

OK, dllhost is not exactly an inspired name but COM Surrogate is hardly clearer. It just puts me in mind of stand-in mothers and biological engineering. Horrid name.

Anyway, certain video codecs seem to fall foul of Data Execution Prevention (DEP), XviD being one. Vista itself may or may not be implicated, I’m not sure. Whichever way, DEP kills the host process, resulting in the error message.

The only cure I have to date is to add dllhost.exe to the list of applications whitelisted for DEP purposes. It is not dreadfully satisfactory. What if some real malware exploited a buffer overrun vulnerability in a dll hosted by the COM Surrogate? I’ve now exempted all dlls running under the COM Surrogate from DEP checks, not just XviD.

I may look for a less troublesome codec. I only picked on XviD because of the recommendations on the youTube website.

PS (added 7 Nov 07):  With hindsight this post is really a precursor to the Vista’s Video Nasties series of posts, so I’m giving it the honorary subtitle of Vista’s Video Nasties #0.

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  1. Hey there just wanted to give you a quick heads up. The words in your post seem to
    be running off the screen in Internet explorer.
    I’m not sure if this is a format issue or something to do with internet browser compatibility but I thought I’d post
    to let you know. The style and design look great though!
    Hope you get the issue solved soon. Many thanks

  2. i have tried for your given solution for as advance system setting for com surrogate but my problem has not not solved so give me other solution

  3. do a scan system mechanic worked for me system cluter and startup programs as well as framentation

  4. Hi i have the same problem with hostdll.exe surrogate, it uses over 60% CPU. i allways kill the process but it comes again and again, i don’t know how to do someone gates a solution? someone has solve this issue?
    thankx in advance
    my configuration : Intel core2 CPU T5200 1.60 GHZ, vista premium sp1, ram 1Gb

  5. hello … for anyone … i got info on an axxo file it was xvid … i downloaded the latest xvid codec and that sorted it

  6. OK, I buy that. Thank you, Matt.

  7. Instead of adding dllhost.exe to the DEP whitelist add xvidcore.dll and xvidvfw.dll located in the system32 folder. No more com surrogate errors 🙂

  8. just for the record, a malware or trojan or something has overrun the dllhost app on my computer so it is possible and there is a risk to whitelisting all dll hosts, and it constantly refreshes my desktop to the point where it takes me 5 minutes to write a post like this one. spybot and norton are useless, i’m going to try kaspersky and see what happens but yes, Vista is the worst OS yet. Ubuntu all the way.

  9. I have problems with suspected malware. The reason for the com surrogate is loading and running strange application ID’s and CLSID and in so doing is playing havoc with my registry.”to boot” moving and running strange applications in the background. I am now at a lost as to what to do?

  10. Has anyone found a solution to the high CPU usage issue? I have a dual CPU machine that runs at 60% until I kill the COM Surrogate process. Shocking…

  11. Argh…I am having this problem right now, it’s CPU usage is fluctuating between 45-60%
    I don’t think it did this before, today I have been playing with some videos though from my phone on here but only in Quicktime, WMP and WMM…I don’t know if this is exactly the same problem but I’m googling around for a solution. =(

  12. Is it normal for COM surrogate to use minimum 50% CPU?

  13. Even an attempt to move the .avi file created with XviD caused a hang. This even after uninstalling the XviD codec. In the end I had to delete the file.

    Have switched over to DivX. So far so good. Encoding results are good, dllhost.exe no longer whitelisted for DEP and to date no hangs, crashes or weird messages about surrogate mothers.

  14. […] unknown: […]

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