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xpcom.dll don't load

  • 7 replies
  • 32 have this problem
  • 6 views
  • Last reply by David A.

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I have a problem whit the xpcom.dll, when the firefox report "can't load xpcom.dll"! But the xpcom.dll is in the firefox folder, and in the system32 folder and in the system too.

I download a new xpcom.dll but the firefox do not start! I deleted the folder of firefox but nothing happened! I reinstall the firefox but the problem persist!

PS: My english is not good.....I speak portuguese.....sorry!

I have a problem whit the xpcom.dll, when the firefox report "can't load xpcom.dll"! But the xpcom.dll is in the firefox folder, and in the system32 folder and in the system too. I download a new xpcom.dll but the firefox do not start! I deleted the folder of firefox but nothing happened! I reinstall the firefox but the problem persist! PS: My english is not good.....I speak portuguese.....sorry!

All Replies (7)

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hello, can you try to do a clean uninstall as it's described in Desinstalando o Firefox (you don't have to delete your configuration though)

afterwards restart your pc, download a fresh copy of firefox from getfirefox.com and install that...

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I make all but the firefox don't start, only the message: "Couldn't load XPCOM"

Thank you!

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hello, the same issue was mentioned here: https://support.mozilla.org/questions/943596 & in this case it was apparently present when firefox was set to autorun on startup of windows.

a general websearch also suggests that it might be related to the sandboxie software - do you use that & run firefox in a sandbox?

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What OS are you using on your computer? Windows XP, Vista, Win 7, Win 8, Mac or Linux?

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(the OP posted with a Google Chrome user agent on Windows 7 (NT 6.1))

Quote: But the xpcom.dll is in the firefox folder, and in the system32 folder and in the system too.

If you have an xpcom.dll file in the system folder and in the system32 folder then you need to remove the file in those locations.

Firefox files should only be in the Firefox program folder.

  • (32 bit Windows) C:\Program Files\Mozilla Firefox\
  • (64 bit Windows) C:\Program Files (x86)\Mozilla Firefox\

Modified by cor-el

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Thanks for help!

I use win 7 32 bits

Modified by escriba

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Is there any simple fast way to correct this "Couldn't load XPCOM" error when I start Firefox?

Thx, David A.

Modified by NoahSUMO