3

I've been having this problem for a while on both Win7 and Win10 machines: When I browse to a folder with a certain kind of file in it -- Specifically, large Quicktime files ~100GB -- Windows seizes for a couple minutes. Everything just stutters and locks up.

If I open up Task Manager or Resource Monitor beforehand I can see that it's a COM Surrogate / dllhost.exe instance that appears to be "chewing through" the huge video file, and the system doesn't become responsive again until it finishes.

After tons of Googling and research, uninstalling software, etc. I still can't figure out what's behind it. I'm assuming it's some software I've installed that attached itself to the shell, but the only way I can figure out what it is is to replicate it (which is very easy) and track what piece of software is creating and using the dllhost instance. How can I do that?

2 Answers 2

1

Run Process Explorer and point the mouse over the dllhost.exe. Now you see a tooltip with the DLL loaded by dllhost.exe

enter image description here

Here it is the thumbnail creating dll. For you this maybe also shown, so disable thumbnails in Explorer options.

1

COM surrogate is responsible for thumbnail generation, as magicandre1981 posted already.

And Raymond Chen [MSFT] notes: "In practice, if you get these types of crashes when browsing folders containing video or media files, the problem is most likely a flaky codec." https://devblogs.microsoft.com/oldnewthing/20090212-00/?p=19173

https://web.archive.org/web/20100126022525/http://blogs.msdn.com/oldnewthing/archive/2009/02/12/9413816.aspx (Alternate link)

Third-party Codecs can be disabled using InstalledCodec.

Additional note:

If you double-click dllhost.exe in Process Explorer, it would show the CLSID hosted by dllhost.exe. If there is one listed, pls post that information here.

(One can lookup the CLSID in the registry to find the corresponding Codec/thumbnail handler, and prevent it from loading.)

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .