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

This thread was closed and archived. Please ask a new question if you need help.

Restore session doesn't work

  • 8 replies
  • 2 have this problem
  • 35 views
  • Last reply by maveet

more options

I'm not sure if this is my Firefox acting up, or just the aftermath of Utorrent installing Web Companion, restoring sessions in Firefox hasn't been possible. Firefox does remember my history, but it shows no options for restoring session or restoring tabs. I've already done a refresh, I've deleted web companion and run CCleaner and Malwarebytes Adwcleaner and they show my system is clean, but I still can't get restore sessions to work.

What's going on, and how can I fix this?

I'm not sure if this is my Firefox acting up, or just the aftermath of Utorrent installing Web Companion, restoring sessions in Firefox hasn't been possible. Firefox does remember my history, but it shows no options for restoring session or restoring tabs. I've already done a refresh, I've deleted web companion and run CCleaner and Malwarebytes Adwcleaner and they show my system is clean, but I still can't get restore sessions to work. What's going on, and how can I fix this?

Chosen solution

jscher2000 said

So --
  • "3-bar" menu button > Restore Previous Session
  • (menu bar) History > Restore Previous Session
-- are missing? Usually that means either (A) the session was restored or (B) the session history file was not found or not usable. If the session was restored, you might find previous session windows and tabs under:
  • "Library" toolbar button > History > Recently Closed Windows (and within each restored window, Recently Closed Tabs)
  • (menu bar) History > Recently Closed Windows (and within each restored window, Recently Closed Tabs)
If there's nothing there, can you think of any reason Firefox might not have saved session history? Some possibilities include:
  • Firefox set to automatic private browsing mode -- if you see previous session history entries, it's not this
  • Firefox set to clear history at shutdown -- if you see previous session history entries, it's not this
  • Utility software removing session history file(s) from your profile folder between sessions -- set CCleaner not to touch session data to rule out CCleaner
  • Odd settings...

Does Undo Close Tab (e.g., Ctrl+Shift+t, or right-click a tab and use the context menu) work?

Could you check for any customized settings here:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful or accepting the risk.

(2) In the search box above the list, type or paste sess and pause while the list is filtered

(3) If either of these are bolded and "modified" to a low number, right-click > Reset them to restore the default value, or double-click to edit the value to something higher:

  • browser.sessionstore.max_tabs_undo (default = 10)
  • browser.sessionstore.max_windows_undo (default = 3)


Thanks for your reply.

So, very weird but this is what I've noticed

1. Using the 3 bar menu to "Restore previous session" does restore my previous session, but Firefox doesn't do this automatically like it used to

2. I have the clock icon in my task bar which I usually used to restore windows or restore tabs. That's the part which is empty every time. My old browsing history however does show up in it and and Ctrl+Shift+T also works.

3. Now here's the weird part, I went to check the "Recently closed windows" and "recently closed tabs" again and it seems that they do show up now. I think hitting the "restore previous sessions" button did something to fix the issue I was having.

So, I think my issue is fixed now. I tried opening new windows and tabs and they show up in the "recently closed windows" and "recently closed tabs" menu.

Weird, but solved I guess.

Read this answer in context 👍 0

All Replies (8)

more options

Hi, can you look to see if it got it all out please : AdAware or Web Companion from Lavasoft.

You can look for a file named dsengine.js in these locations. You should only find channel-prefs.js in the "defaults\pref" location. Any file found here apart from channel-prefs.js is suspicious. You can check the content of the file in a text editor (use open with and do not double-click the file).

C:\Program Files\Mozilla Firefox\defaults\pref\ C:\Program Files (x86)\Mozilla Firefox\defaults\pref\

You can look for a file named dsengine.cfg in the main Firefox program folder. C:\Program Files\Mozilla Firefox\ C:\Program Files (x86)\Mozilla Firefox\ Delete the dsengine.js and dsengine.cfg files when present.

So running A Beta, you may have to uninstall and run the installer again if it does not turn up. It does not touch your Profile when doing this.

Please let us know if this solved your issue or if need further assistance.

more options

Pkshadow said

Hi, can you look to see if it got it all out please : AdAware or Web Companion from Lavasoft. You can look for a file named dsengine.js in these locations. You should only find channel-prefs.js in the "defaults\pref" location. Any file found here apart from channel-prefs.js is suspicious. You can check the content of the file in a text editor (use open with and do not double-click the file). C:\Program Files\Mozilla Firefox\defaults\pref\ C:\Program Files (x86)\Mozilla Firefox\defaults\pref\ You can look for a file named dsengine.cfg in the main Firefox program folder. C:\Program Files\Mozilla Firefox\ C:\Program Files (x86)\Mozilla Firefox\ Delete the dsengine.js and dsengine.cfg files when present. So running A Beta, you may have to uninstall and run the installer again if it does not turn up. It does not touch your Profile when doing this. Please let us know if this solved your issue or if need further assistance.

So I just tried what you said. First of all, the folder for Mozilla was not present in program files or program files(x86). I reinstalled Firefox and the folder Mozilla showed up in C:\Program Files\Mozilla. I could only find the file channel-prefs.js.

I still have the issue of the sessions not showing up for restore, but my history is present.

more options

So --

  • "3-bar" menu button > Restore Previous Session
  • (menu bar) History > Restore Previous Session

-- are missing? Usually that means either (A) the session was restored or (B) the session history file was not found or not usable.

If the session was restored, you might find previous session windows and tabs under:

  • "Library" toolbar button > History > Recently Closed Windows (and within each restored window, Recently Closed Tabs)
  • (menu bar) History > Recently Closed Windows (and within each restored window, Recently Closed Tabs)

If there's nothing there, can you think of any reason Firefox might not have saved session history? Some possibilities include:

  • Firefox set to automatic private browsing mode -- if you see previous session history entries, it's not this
  • Firefox set to clear history at shutdown -- if you see previous session history entries, it's not this
  • Utility software removing session history file(s) from your profile folder between sessions -- set CCleaner not to touch session data to rule out CCleaner
  • Odd settings...

Does Undo Close Tab (e.g., Ctrl+Shift+t, or right-click a tab and use the context menu) work?

Could you check for any customized settings here:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful or accepting the risk.

(2) In the search box above the list, type or paste sess and pause while the list is filtered

(3) If either of these are bolded and "modified" to a low number, right-click > Reset them to restore the default value, or double-click to edit the value to something higher:

  • browser.sessionstore.max_tabs_undo (default = 10)
  • browser.sessionstore.max_windows_undo (default = 3)
more options

Chosen Solution

jscher2000 said

So --
  • "3-bar" menu button > Restore Previous Session
  • (menu bar) History > Restore Previous Session
-- are missing? Usually that means either (A) the session was restored or (B) the session history file was not found or not usable. If the session was restored, you might find previous session windows and tabs under:
  • "Library" toolbar button > History > Recently Closed Windows (and within each restored window, Recently Closed Tabs)
  • (menu bar) History > Recently Closed Windows (and within each restored window, Recently Closed Tabs)
If there's nothing there, can you think of any reason Firefox might not have saved session history? Some possibilities include:
  • Firefox set to automatic private browsing mode -- if you see previous session history entries, it's not this
  • Firefox set to clear history at shutdown -- if you see previous session history entries, it's not this
  • Utility software removing session history file(s) from your profile folder between sessions -- set CCleaner not to touch session data to rule out CCleaner
  • Odd settings...

Does Undo Close Tab (e.g., Ctrl+Shift+t, or right-click a tab and use the context menu) work?

Could you check for any customized settings here:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful or accepting the risk.

(2) In the search box above the list, type or paste sess and pause while the list is filtered

(3) If either of these are bolded and "modified" to a low number, right-click > Reset them to restore the default value, or double-click to edit the value to something higher:

  • browser.sessionstore.max_tabs_undo (default = 10)
  • browser.sessionstore.max_windows_undo (default = 3)


Thanks for your reply.

So, very weird but this is what I've noticed

1. Using the 3 bar menu to "Restore previous session" does restore my previous session, but Firefox doesn't do this automatically like it used to

2. I have the clock icon in my task bar which I usually used to restore windows or restore tabs. That's the part which is empty every time. My old browsing history however does show up in it and and Ctrl+Shift+T also works.

3. Now here's the weird part, I went to check the "Recently closed windows" and "recently closed tabs" again and it seems that they do show up now. I think hitting the "restore previous sessions" button did something to fix the issue I was having.

So, I think my issue is fixed now. I tried opening new windows and tabs and they show up in the "recently closed windows" and "recently closed tabs" menu.

Weird, but solved I guess.

more options

Hi Drinky, automatic restore is one of the Startup settings:

  • Windows: "3-bar" menu button (or Tools menu) > Options
  • Mac: "3-bar" menu button (or Firefox menu) > Preferences
  • Linux: "3-bar" menu button (or Edit menu) > Preferences
  • Any system: type or paste about:preferences into the address bar and press Enter/Return to load it

Wow, this must have been re-organized recently... There's now a checkbox right near the top for "Restore previous session" instead of the old radio button layout.

more options

I've been having this problem for some time. When I type sess into about:config I get nothing...blank page. Restore session is ticked in preferences. History lists restore tabs, but not windows. 3bar preferences doesn't offer restore. Preferences, Privacy and Security is set on Remember history.

I've been using Tab Session Manager when there's not other option, but it often hangs. Often it seems to be restoring tabs (I've got about 300, since I'm researching things and am slow to eliminate pages), but in fact, only lists long titles, preceded by mozextension (gibberish to me) string of letters. Like this: Killing Eve: how my psycho killer was brought to life | Television & radio | The Guardian moz-extension://1a734a37-97f7-924d-9fc0-c88f71832395/replaced/replaced.html?state=redirect&title=Killing%20Eve%3A%20how%20my%20psycho%20killer%20was%20brought%20to%20life%20%7C%20Television%20%26%20radio%20%7C%20The%20Guardian&url=https%3A//www.theguardian.com/tv-and-radio/2018/aug/05/killing-eve-how-my-psycho-killer-was-brought-to-life-luke-jennings&favIconUrl=https%3A//assets.guim.co.uk/images/favicons/48bc5564bb01b74cf7cd1a08ae0dd98e/32x32.ico


I've tried other restore session add-ons, but haven't found anything better. I've turned off all other add-ons that might influence tab behavior, like Tab suspender and Tab for a cause. Again, these add strings of extension labels, which I then have to sort through to try and find the url to manually open.

Is this really about too many tabs? I'm so very frustrated. I'd eliminate some windows if I could, but I'm too slow to keep up. For awhile I thought my problems meant I needed to upgrade, but that never helped. Now I just keep clicking Not Now when prompted to upgrade, unless there's security upgrade. I'm ready to switch to Vivaldi, although I love FF and the add-ons that make life easier for me. But this frustration is getting too much. Help please. thx.

Modified by maveet

more options

Hi maveet, could you start a new thread?

Your last Firefox question was on Mac, while the user who asked this question is on Windows, and as that time, you had a lengthy list of add-ons. I can assure you that it will be less confusing for everyone if you post a new question with your own Firefox configuration info than if we try to work on it here.

https://support.mozilla.org/questions/new/desktop/fix-problems

As always, scroll down past article suggestions to continue with the new question form.

more options

thanks.