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My previously open tabs keep disappearing, and I've tried everything Mozilla has suggested, but nothing works.

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I'm using Windows XP, and I've tried session restore through History (it is grayed out), and typed "about:sessionrestore" into the URL bar (it lists nothing), and I looked for the file "sessionrestore.js" but it doesn't exist (only "sessionstore.js" and "sessionstore-1.js"). I'm using Firefox version 31.0 and it has lost my tabs twice in two days. Thanks for your help.

I'm using Windows XP, and I've tried session restore through History (it is grayed out), and typed "about:sessionrestore" into the URL bar (it lists nothing), and I looked for the file "sessionrestore.js" but it doesn't exist (only "sessionstore.js" and "sessionstore-1.js"). I'm using Firefox version 31.0 and it has lost my tabs twice in two days. Thanks for your help.

All Replies (14)

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The names of the files are correct (no "re" in the middle).

If you look at the modified date/time of the sessionstore-1.js file, does it seem likely to have the tabs you're looking for?

A numbered file is created when Firefox is having problems updating sessionstore.js. Windows may have had a lock on it, or it might be corrupted.

If you want to try using sessionstore-1.js, please post back for recovery procedures. And before renaming or deleting anything, please back up all your sessionstore files to a safe location, such as your Documents folder.

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Thank you jscher2000 for the response. Yes, the file is large(ish) and the date looks right, so I suspect it might be the correct one. I'm glad you mentioned to back up that file. I did, and as you said, I will need help knowing what to do with it or how to perform recovery procedures. Thanks so much.

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You can swap in the sessionstore-1.js file in place of sessionstore.js, but you have to exit out of Firefox first. Once Firefox finishes its clean-up (various timestamps will get updated), you can rename sessionstore.js to sessionstore.old and rename sessionstore-1.js to sessionstore.js. The next time you start Firefox, depending on your startup setting, it will restore the "new" sessionstore.js or you can restore it from the History menu. Any luck?

It's probably a good idea to check in a few hours that Firefox is actually updating sessionstore.js now and not creating a new sessionstore-1.js file.

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When I do this (and I've done it a few times now), firefox simply erases the "new" sessionstore.js file and creates a new one (which is only 1 kb, and opens with 1 tab - the session restore tab). I still have the old sessionstore-1.js file saved in a separate place, so I can keep renaming it and trying it again, but that's the result I've gotten every time so far.

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Is there any non-text (binary) data in the sessionstore-1.js file if you check this in a text editor or hex file viewer?

You can open the file in the Scratchpad (Firefox/Tools > Web Developer). Click the "Pretty Print" button to format the file for readability.

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I'm not sure what "non-text (binary) data" is, but I opened it in scratchpad, like you said, and only saw text. What should I be looking for there? Thanks for the help.

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If there is only text in the file and it doesn't look corrupted otherwise if you scroll down to the bottom then the file should work. You can check (search) the file for the presence of a comma right before a closing bracket (i.e. "],}" without quotes) indicating a missing or empty section. If the file is OK then you should see the tabs and windows from that session after you have placed this file as sessionstore.js in the profile folder with Firefox closed. You may have to see if you have a "Restore Previous Session" in the history menu or "History > Recently Closed Tabs/Windows".

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I tried all of those things, and nothing worked, unfortunately. I checked and there was no comma right before a closing bracket. Also, firefox refuses to accept any "sessionstore.js" file that I try to place in the profile folder, no matter how many ways I try.

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Did you check for a "Restore Previous Session" in the History menu?

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Yes. But it is always grayed out. It lists it, but is unclickable.

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It may be time to try some alternate methods of scrounging URLs out of the file.

If the file structure is intact:

If those give errors because the file structure is damaged:

You can scrounge the URLs out of the file using Microsoft Word and a VBA macro. I tested on a small file (250K). Not sure whether it can handle extremely large files. You may want to turn off all proofing in Word before opening sessionstore.js since spellchecking and grammar-checking often crap out on large documents.

http://pastebin.com/iK6x2i1N

I noticed there is an "index" property for each tab indicating which page from history was showing. Usually it was the last page so I didn't take the time to extract it. However, if you didn't want all the full tab history and just wanted the displayed page, you would need to do that.

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I'm so sorry for the long absence. Firefox lost my tabs three more times over the course of me trying to use the solutions you offered, so I started to get too frustrated and discouraged. I didn't want to give up, however, without acknowledging all the assistance I was offered, and to really thank you guys for the help. I do appreciate it, and I'm still trying to figure out my next move since nothing seems to work. I love Firefox, but this glitch is kind of a big deal. We'll just have to see, but I wanted to make sure I thanked you before you thought I'd completely forgotten about you.

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Is the the problem that Firefox keeps create new numbered sessionstore-#.js files or has the problem changed?