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Cannot install web developer because: Invalid file hash (possible download corruption) -261

  • 4 replies
  • 14 have this problem
  • 7 views
  • Last reply by cor-el

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I cannot access my web developer tasks anywhere. I tried to install again but got this message: because: Invalid file hash (possible download corruption) -261

I cannot access my web developer tasks anywhere. I tried to install again but got this message: because: Invalid file hash (possible download corruption) -261

All Replies (4)

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Try to enable third-party cookies temporarily during the download and installation of the extension. --- Enhanced Tracking Protection in Firefox for desktop Third-party cookies and Firefox tracking protection

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Since 3.6.6 I've been having the same problem. Not just one extension but on several.

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Save the xpi file to your desktop and install the extension by dragging the file in a Firefox tab or use File > Open File. See also http://kb.mozillazine.org/Unable_to_install_themes_or_extensions

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I'd checked everything from that website without success. Things worked fine with 3.6.4. It seemed to have broken with 3.6.6. Would a re-install help??