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Why does Firefox 31 change all PDF icons and opening in browser, require a fix using REGEDIT to fix for ALL USERS on a computer?

  • 2 replies
  • 2 have this problem
  • 1 view
  • Last reply by cor-el

thekops
thekops
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The solution to use REGEDIT in the question linked below almost fixed my trouble with PDF files on over 30 computers, with several users on each computer: https://support.mozilla.org/en-US/questions/1013642

But I needed to fix it for ALL users on a computer, without logging onto each account, on each computer. My fix was to logon as administrator and change the following system-global key instead:

HKEY_LOCAL_MACHINE\Software\Classes\.pdf

Name: Default Type: Reg_SZ Data: FirefoxHtm

Changed the data from FirefoxHtm to AcroExch.Document.11

I use Adobe Reader XI on Win7 Pro, 64-bit machines. The problem started when I ran a downloaded file to install the new version of Firefox on the computers.

Why would Firefox require me to use REGEDIT in this manner to fix the problem?

The solution to use REGEDIT in the question linked below almost fixed my trouble with PDF files on over 30 computers, with several users on each computer: https://support.mozilla.org/en-US/questions/1013642 But I needed to fix it for ALL users on a computer, without logging onto each account, on each computer. My fix was to logon as administrator and change the following system-global key instead: HKEY_LOCAL_MACHINE\Software\Classes\.pdf Name: Default Type: Reg_SZ Data: FirefoxHtm Changed the data from FirefoxHtm to AcroExch.Document.11 I use Adobe Reader XI on Win7 Pro, 64-bit machines. The problem started when I ran a downloaded file to install the new version of Firefox on the computers. Why would Firefox require me to use REGEDIT in this manner to fix the problem?

Chosen solution

This only happens when you set Firefox as the default browser and Firefox thinks that there is currently no application the handles PDF files.

Read this answer in context 👍 1

All Replies (2)

the-edmeister
the-edmeister
  • Moderator
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As explained in that question thread, it is a regressive Bug that occurred in Firefox 31.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Chosen Solution

This only happens when you set Firefox as the default browser and Firefox thinks that there is currently no application the handles PDF files.