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Why did the recent update switch from 64-bit to 32-bit on a 64-bit Windows 10 box?

  • 6 replies
  • 37 have this problem
  • 1 view
  • Last reply by jclarkw

pstieber
pstieber
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I'm running a 64-bit version of Windows 10 Pro. I just used Help | About Firefox to update. i was running a 64-bit version of Firefox. The update to 51.0.1 switched to a 32-bit version. Why did it switch from 64 to 32-bit version?

I'm running a 64-bit version of Windows 10 Pro. I just used Help | About Firefox to update. i was running a 64-bit version of Firefox. The update to 51.0.1 switched to a 32-bit version. Why did it switch from 64 to 32-bit version?

Chosen solution

it is indeed: https://bugzilla.mozilla.org/show_bug.cgi?id=597738

Read this answer in context 👍 3

All Replies (6)

cor-el
cor-el
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Sometimes it seems to happen that you switch to a 32 bit version or even another language when updating. Maybe this happens because security software in locking files and thus forces Firefox to download a full update instead of a partial update.

The current release shows the version including 32 bit or 64 bit in "Help > About". Your System Details list next to the question shows that you use a 32 bit Firefox 51 version (WOW64).

  • Mozilla/5.0 (Windows NT 10.0; WOW64; rv:51.0) Gecko/20100101 Firefox/51.0

If you want to use the 64 bit version then download this version here:

Note that only the Shockwave Flash plugin and Silverlight plugins are enabled for 64 bit Firefox versions for Windows. If you need to use other plugins like Java or media players then install the 32 bit Firefox release.

James
James
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Are you sure you were indeed using the 64-bit (Win64) version before the update?

If you downloaded Firefox from www.mozilla.org then Windows users are served the 32-bit version so you need to download from www.mozilla.org/firefox/all/ to get Win64 Firefox.

Modified by James

pstieber
pstieber Question owner
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I thought I was running a 64-bit version. Another possibility may be that version 51.0.1 is the first version to indicate "(32-bit)" in the about dialog under Windows. Is that the case?

philipp
philipp
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Chosen Solution

it is indeed: https://bugzilla.mozilla.org/show_bug.cgi?id=597738

pstieber
pstieber Question owner
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Thank for all of the help.

I'm concluding I was incorrect about having a 64-bit version installed initially and was fooled by the new (32-bit) info in the about dialog.

Thanks again!

jclarkw
jclarkw
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James said

Are you sure you were indeed using the 64-bit (Win64) version before the update?...

In my case I'm not sure this matters. Whatever it was I was running (I THINK I deliberately installed 64-bit Firefox many updates ago, definitely under 64-bit Windows 7 SP1), I was able to print Web pages just fine until the 51.0.1 update. Now I get the attached error message whenever I print from Firefox, either directly to my printer or to Acrobat.

It really appears that the update caused this problem. Any suggestions? -- jclarkw