Additionally, it is also resetting the contents of the navigation toolbar back to default every time I start.

I am really upset about this. I'm going to try to fall back to the previous version of Firefox if it isn't fixed fast.

In the location bar at the top, type about:config and hit Enter

1. In the filter at the top, type keyword.URL
2. Double click it and replace the current setting with http://www.google.com/search?q= (it has to be entered exactly as you see it written here)
3. Close Firefox via File | Exit

This will reset your homepage to Google.

Then go to How to set the home page to save it to whatever you wish.

P.S. Sorry it took so long to respond to your question.

See also:

• http://kb.mozillazine.org/Preferences_not_saved
• http://kb.mozillazine.org/Session_Restore

Are you using cleanup software like CCleaner ?

I have tried ALL of the troubleshooting/repair steps listed here. NONE of them fixed the problem.

The problem doesn't happen every time I exit firefox and later start it up again. But it probably happens at least 1 third of the time.

When it happens, my session is not restored (and about:sessionrestore shows 3 windows when I only had 1 window open, and it shows only 1 of the tabs I had opened). Additionally, my customizations of the buttons appearing on the main toolbar are lost/reset to default.

Note that I upgraded from Firefox 3.6.15.

Please try running Firefox in Diagnose Firefox issues using Troubleshoot Mode. If it functions properly in that configuration, then one of your add-ons is the culprit.

Also, in Tools | Options | Advanced, uncheck "Tell websites I don't want to be tracked" if it's enabled.

Similarly, disable the no tracking feature in NoScript if that's also enabled.

Tell websites I don't want to be tracked" is NOT enabled.

I don't see any "no tracking" feature in NoScript.

All of my add-ons worked fine with firefox 3.6, and firefox 4 disabled several that it considers "not compatible", so I expect that firefox 4 should be fine with the remaining add-ons (of which the list is attached to this request)>

Is safe mode still going to restore my session and my toolbar? If not it won't help me. If it does, how am I supposed to tell the difference between safe mode eliminated the problem vs. it simply didn't happen this time? The fact that the problem is intermittent makes it harder to troubleshoot. And I need for noscript and roboform to be working when I do my normal browsing, so if safe mode is disabling those then running with safe mode doesn't help me.

BTW, I've noticed a couple other problems with firefox 4 that didn't happen with firefox 3.6 (don't know if any are related):

1) If I right-click a link and click open in a new window, the new window appears but the tab is empty. Only open in a new tab works correctly.

2) When I type in the google toolbar's search box and click one of the suggestions from its list, it does NOT automatically search (like it did in firefox 3.6) and while the droplist disappears (as if it recognized that I clicked), the search box content still contains only what I typed.

Could you update your Norton using the recently released compatibility patch and see if that makes any difference? See Norton Compatibility Firefox patch 4.0

"Tell websites I don't want to be tracked" only makes Firefox send a specific HTTP header (DNT=1) to a server. That can never cause any real problems AFAIK.

This can be a problem with the files sessionstore.js and sessionstore.bak in the Profile Folder

Delete sessionstore.js and sessionstore.bak in the Profile Folder

• Help > Troubleshooting Information > Profile Directory: Open Containing Folder

If you see files sessionstore-##.js with a number in the left part of the name like sessionstore-1.js then delete those as well.

You will have to redo App Tabs and Tab Groups after deleting sessionstore.js.

See:

• http://kb.mozillazine.org/Session_Restore

So I just noticed something odd. I had to reboot after installing the Norton 360 hotfix mentioned above. Before I closed down firefox, I had printed a credit card statement. The bank's web site opened a 2nd window to access the link to the pdf file of the statement. I closed that window after printing the statement (via adobe reader).

So I had 1 window open with a bunch of tabs open (none of which were to my bank). I closed firefox (by clicking the X in the top right corner) and rebooted my system.

When I started firefox again (after rebooting), it opened 1 window, but that window contained a single tab which was the logon page to my bank! Its like a partial session was saved close to an hour before I closed firefox, and that's what got restored! Really weird.

I tried about:sessionrestore at that point, and it showed a list of 2 windows, 1 with a single blank tab and one with my banks logon. None of the tabs that were open when I last closed firefox were shown.

Anyway, I exited firefox and deleted the sessionstore files and then restarted firefox. We'll see what happens later this week -- if it behaves or it if continues to exhibit weird behavior.

OK, there is definitely something funky with opening additional windows. The session restore worked fine for a few days, but then broke this morning. The sessionstore.bak file (which has the time stamp of when I shut down the browser last night) has the following. What is interesting is that that it contains entries for more than one window and it includes tabs that I had closed several hours before.

What is more interesting is that on restore, only the tab from the 1st window is open. Firefox came up with 3 windows open, but the other 2 had no tabs open at all.

My conclusion is that as soon as I try to open more than 1 window in Firefox 4, the session saving stops working correctly and/or the session file gets corrupted.

I don't have enough room to post the whole sessionstore file here, so if someone wants to look at it, please provide a way to upload/send a zip file.

{"windows":[{"tabs":[{"entries":[{"url":"https://www.us.hsbc.com/1/2/3/personal/online-services/personal-internet-banking/calendar?isUrlRedirect=yes&urlRedirectCommand=cmd_CalendarPopUpView","title":"Calendar","ID":82,"docshellID":51,"referrer":"https://www.us.hsbc.com/1/2/3/personal/online-services/personal-internet-banking/transfers/between-accounts?isUrlRedirect=yes&urlRedirectCommand=cmd_TransferContinue","docIdentifier":97},{"url":"https://www.us.hsbc.com/1/2/3/personal/online-services/personal-internet-banking/calendar?isUrlRedirect=yes&urlRedirectCommand=cmd_CalendarPopUpView","title":"Calendar","cacheKey":1303647164,"ID":83,"docshellID":51,"referrer":"https://www.us.hsbc.com/1/2/3/personal/online-services/personal-internet-banking/calendar?isUrlRedirect=yes&urlRedirectCommand=cmd_CalendarPopUpView","docIdentifier":98}],"index":2,"hidden":false,"attributes":{"image":"https://www.us.hsbc.com/favicon.ico"}}],"selected":1,"_closedTabs":[],"isPopup":true},{"tabs":[{"entries":[],"hidden":false,"attributes":{}}],"selected":1,"_closedTabs":[]},{"tabs":[{"entries":[],"hidden":false,"attributes":{}}],"selected":1,"_closedTabs":[]}],"selectedWindow":0,"_closedWindows":[{"tabs":[{"entries":[{"url":"https://www.facebook.com/?ref=home","title":"Facebook","ID":2271891127,"docshellID":25,"docIdentifier":1},{"url":"https://www.facebook.com/?sk=lf","title":"Facebook","ID":2271891128,"docshellID":25,"referrer":"https://www.facebook.com/?ref=home","docIdentifier":3,"stateData":"\"https://www.facebook.com/?sk=lf\"","children":[{"url":"https://0-201.channel.facebook.com/iframe/11?r=https%3A%2F%2Fs-static.ak.facebook.com%2Frsrc.php%2Fv1%2Fyf%2Fr%2FqlO-v-YlryA.js&r=https%3A%2F%2Fs-static.ak.facebook.com%2Frsrc.php%2Fv1%2Fyv%2Fr%2F4qcjb7JiGFM.js&r=https%3A%2F%2Fs-static.ak.facebook.com%2Frsrc.php%2Fv1%2Fyu%2Fr%2FHg7Vn6TvZea.js&r=https%3A%2F%2Fs-static.ak.facebook.com%2Frsrc.php%2Fv1%2FyB%2Fr%2FHeHjejZj1Ft.js&r=https%3A%2F%2Fs-static.ak.facebook.com%2Frsrc.php%2Fv1%2FyI%2Fr%2FTF8WVXsmqcX.js","ID":2271891129,"docshellID":36,"referrer":"https://www.facebook.com/?sk=lf","docIdentifier":5}]},{"url":"https://www.facebook.com/","title":"Facebook","subframe":true,"ID":2271891130,"docshellID":25,"docIdentifier":3,"stateData":"\"https://www.facebook.com/\"","children":[{"url":"https://0-201.channel.facebook.com/iframe/11?r=https%3A%2F%2Fs-static.ak.facebook.com%2Frsrc.php%2Fv1%2Fyf%2Fr%2FqlO-v-YlryA.js&r=https%3A%2F%2Fs-static.ak.facebook.com%2Frsrc.php%2Fv1%2Fyv%2Fr%2F4qcjb7JiGFM.js&r=https%3A%2F%2Fs-static.ak.facebook.com%2Frsrc.php%2Fv1%2Fyu%2Fr%2FHg7Vn6TvZea.js&r=https%3A%2F%2Fs-static.ak.facebook.com%2Frsrc.php%2Fv1%2FyB%2Fr%2FHeHjejZj1Ft.js&r=https%3A%2F%2Fs-static.ak.facebook.com%2Frsrc.php%2Fv1%2FyI%2Fr%2FTF8WVXsmqcX.js","subframe":true,"ID":2271891129,"docshellID":36,"referrer":"https://www.facebook.com/?sk=lf","docIdentifier":5},{"url":"https://www.facebook.com/ai.php?aed=AQCm_0ik51YyeLRA9yw1ZJnyT2nzu_q12wZHcHGBv6w5pp9CgqVAaVG2tKj6bVEMo7hhOng5GQYYPPoTj0DQh3oG1zjFO3aJFvuRjpVorebIExAC_kFYVgd2okAhQitAU_x9FrEMgsmR8fN9BTeX2vDI4Daz2Puih8LrFJDfEQx5qBObqJPE5IS1V8EX3pIrpOBShxxwyjAgmQhmUi1pVCzeUQgBVL-2z77WF1HQn7vTh0S1fP_LKhLbZX_4kGiZXsaiQYLaetzGA_Jq7UEE3H3fRF_JhPtRaVcfJ0TiBS4Kji3dod50M-v4osK-01KmeCupjhg_qJVMeJhuRl5npz58HDsWCUqWUWUaOn4HP1SdekStiFpt2fL12yFYCHKYZrtsBn2lkhTmbzOfc44IGdV7e1ZhCetpYpZSh0j0-

Can you try doing the following please.

In the location bar, type: about:config and hit Enter.

In the filter at the top, copy/paste the following: browser.sessionstore.max_concurrent_tabs

Double click it and change the default which is "3" into "0".

Close Firefox and restart it again.

Silly question perhaps, but you don't happen to have "Clear history when Firefox closes" checkmarked by any chance? The setting is located in Tools | Options | Privacy.

Changed max_concurrent_tabs -- that didn't help.

History is set to - Remember History.

The problem is definitely triggered by having opened a 2nd firefox window.

As long as I have opened only 1 firefox window, I don't have any problems.

As soon as I open a 2nd window (or a 2nd window is opened by a web site script), the session will not restore correctly the next time I exit and restart firefox.

I tested this by right-clicking on a link and clicking open in a new window. Incidentally, whenever I do that, the new window always opens with a single blank (new) tab and with a toolbar arrangement that does not match what the original window looks like. The newly opened window never shows the web page that I asked to open (via right click).

Dragging a tab from the original window to the newly opened window also doesn't work.

FWIW, this is on 64 bit Windows 7.

You could maybe try this add-on to see if it makes any difference: https://addons.mozilla.org/en-US/firefox/addon/session-manager/

The addon session manager was working fine for a few days. But this morning I accidentally closed Firefox and when I reopened it, I got a single window restored that was a popup offer. The tabs I was actually viewing didn't appear. I was able to restore a previous session (from the night before) but not exactly what I had open before accidentally closing firefox.

Incidentally, this is now with Firefox 4.0.1.

Who was the pop-up offer from?

Also, do you by any chance have chat utility installed called Digsby?

No, I don't have Digsby (or any other chat utility) installed.

I think the pop-up offer was from one of my credit cards (after I had logged in to view my statement).

Could you please try the suggestion on this page. The author seems to have had the same problem as yourself. http://www.ghacks.net/2010/12/25/firefox-4-session-restore-not-working-try-this-fix/

Everything the article suggests, I have already tried in the past. NOTHING is configured to be deleted on exit. ALL history is set to be saved.

Yes, I understand that, but what the author of that article is suggesting is that you set Firefox up in the same way as he did, that is to say, checkmark "Clear History when Firefox closes", but in the submenu, uncheck "Browsing History".

Or did you try that already?

I didn't think he was saying to do that. He seems to be saying that if you have custom settings and clear history when firefox closes, to make sure you uncheck browsing history.

I have it set to remember history, so nothing is being cleared.