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Firefox does not open Filetypes from Windows File Handler

Christoph Fink
Christoph Fink
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I can't open Files from Firefox on a Windows Terminal Server. Whenever I try to open a downloaded file by clicking on it (or specifying "open with" on the download Dialog) nothing gets opened and no errors are shown.

Usually it opens the default program specified in Windows but on 2 Terminal Servers nothing opens.

What I tried so far:

  • Check filetype associations in Windows and testet it on a cmd and the windows explorer: works as expected
  • Try with different Windows Users: Problem is present across different windows users
  • Try with a new firefox profile: Same problem
  • Try with firefox.exe -safe-mode: Same problem
  • Try resetting handlers.json (by moving from the Firefox installation directory)

Do you have any ideas how to investigate this further?

I know that it worked previously. Could this be caused by a Update of Firefox?

I can't open Files from Firefox on a Windows Terminal Server. Whenever I try to open a downloaded file by clicking on it (or specifying "open with" on the download Dialog) nothing gets opened and no errors are shown. Usually it opens the default program specified in Windows but on 2 Terminal Servers nothing opens. What I tried so far: * Check filetype associations in Windows and testet it on a cmd and the windows explorer: works as expected * Try with different Windows Users: Problem is present across different windows users * Try with a new firefox profile: Same problem * Try with firefox.exe -safe-mode: Same problem * Try resetting handlers.json (by moving from the Firefox installation directory) Do you have any ideas how to investigate this further? I know that it worked previously. Could this be caused by a Update of Firefox?

All Replies (2)

crankygoat
crankygoat
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You may want to check your Event Logs or trace what happens with Sysinternals Process Monitor. Maybe a file (not user) permissions problem?

Christoph Fink
Christoph Fink Question owner
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I procmon I can see that it searches for the program in the registry and finally tries to open AcroRD32.exe with the appropriate path of that executable. After that there's a QueryOpen Operation with the path of the PDF File (but nothing further after that). I copied the path of the executable and the PDF File in a cmd within the session and it opens just fine. Only within Firefox there's no Window appearing. This tells me that permissions are fine (Acrobat Reader can be opened and the file too). Nothing relevant shows up in the Windows eventlogs though (so no appcrashes or similar stuff)