I got sick of video files being locked when I was moving stuff around. The reason they were being locked is that Windows Explorer would open up the file to create a thumbnail while I was browsing without releasing the handle properly.
Normally I'd use Process Explorer to unlock it, but this was happening far too often in a day to put up with.
If you want to disable thumbnails for videos, many sites will tell you to use this command:
regsvr32 /u shmedia.dll
Well that works fine, but you also give up the ability to view ID3 tags on MP3 files and other audio/video formats.
I wanted to keep this functionality, so I had to use another method.
- Open up RegEdit
- Navigate to "HKEY_CLASSES_ROOT\.avi\ShellEx"
- Expand the path and check the default value.
Now for the tricky bit. If the default value is "{c5a40261-cd64-4ccf-84cb-c394da41d590}", then feel free to change it to an empty string (by deleting the text and clicking OK).
Otherwise, copy the value and go to "HKEY_CLASSES_ROOT\CLSID\{your-key-value}\InProcServer32". For me, it was "HKEY_CLASSES_ROOT\CLSID\{c5a40261-cd64-4ccf-84cb-c394da41d590}\InProcServer32".
If the default value has "shmedia.dll" in it, then feel free to go back to the .avi key and delete your key from the default value.
Now, no more thumbnails for just AVI files. You can perform this for other filetypes and the method would remain the same.
