Com Surrogate high CPU usage in Task Manager

[stealth30]

Every time I open a folder in Icons View with a bunch of pdf and epub files and thumbnails start generating eventually Task Manager will show a Com Surrogate process with high CPU usage. The process is related to a dll file in the System folder that seems to be legit. This issue was non existent before DarkThumbs install, so it has to be related to it. Any feedback? Thanks

[fire-eggs]

As I mentioned in Discussion #73, DarkThumbs does not create PDF thumbnails. So if you could narrow down the issue to EPUB vs PDF, that could help.

Can you identify the DLL file in question? DarkThumbs does not install any DLLs into the System folder, but I'm sure it uses some.

[stealth30]

UPDATE: Ok, the issue just showed up again, the process in Task Manager is called "COM Surrogate" and the DLL file is the dllhost.exe in c:\Windows\System32 . This happens when I have many epub files in a certain folder and as I browse through the folder with Windows Explorer the thumbnails are being generated but sometimes the thumbnail generation gets stuck and a green bar in the address bar of Windows Explorer advances very slowly and seems to never finish, leaving the epub icons without their thumbnails, and eventually the wait is so long that I end the task with Task Manager

[fire-eggs]

Thank you very much for the additional info. This sounds very annoying, I'm sorry to hear that DarkThumbs is having these problems.

With the comment "sometimes the thumbnail generation gets stuck", it sounds like certain epubs might be causing difficulties for DarkThumbs. If it wouldn't be too much trouble, could you provide more details about the
the epubs in that "certain folder"? Can you tell me where I might get them so as to investigate what's going on?

Thank you,
fire-eggs

[stealth30]

Thanks Fire for the reply. The issue is not EPUB specific, it is random and happens with ANY EPUB. At first thumbnails are generated without issue and as I browse the folder containing the EPUBs they continue to show thumbnails correctly. Eventually thumbnails stop being generated as if the process would halt and the COM Surrogate fires with high CPU. I tried waiting a few minutes to see if the process stops, but it doesn't, with the PC activating fans due to high CPU, so I'm forced to end the process from Task Manager.
Before installing DarkThumbs I was able to generate EPUB thumbnails by adding some lines to the registry which I can't recall, that I found many years ago in a ebook reader forum, and it worked fine. Being that I discovered DarkThumbs I thought that it'd be cool to have such app without the need of hacking the registry.