We're calling on all EU-based Mozillians with iOS or iPadOS devices to help us monitor Apple’s new browser choice screens. Join the effort to hold Big Tech to account!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Le thread ibilondoloziwe. Nceda ubuze umbuzo omtsha ukuba ufuna uncedo.

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 iimpendulo
  • 2 inale ngxaki
  • 1 view
  • Impendulo yokugqibela ngu cor-el

thekops
thekops
more options

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?

Isisombulu esikhethiweyo

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

Funda le mpendulo kwimeko leyo 👍 1

All Replies (2)

the-edmeister
the-edmeister
  • Moderator
more options

As explained in that question thread, it is a regressive Bug that occurred in Firefox 31.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

Isisombululo esiKhethiweyo

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