Okay, you close and reopen Firefox, No problem. You shut down the computer, problem.

Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.

You can try these free programs to scan for malware, which work with your existing antivirus software:

• Microsoft Safety Scanner
• MalwareBytes' Anti-Malware
• Anti-Rootkit Utility - TDSSKiller
• AdwCleaner (for more info, see this alternate AdwCleaner download page)
• Hitman Pro
• ESET Online Scanner

Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista/XP if you don't already have one.

Further information can be found in the Troubleshoot Firefox issues caused by malware article.

Did this fix your problems? Please report back to us!

About history;

Press the Alt or F10 key to bring up the tool bar. Then select History. Hot key is <Control>(Mac:<Command>)<Shift> H. Does everything look okay?

Type about:preferences#privacy <Enter> in the address bar.

The button next to History, select Use Custom Settings.

Turn off Always use private browsing mode Turn on Remember my browsing and download history

At the bottom of the page, turn on Clear History When Firefox Closes. At the far right, press the Settings button. Turn on ONLY Cache and Form And Search History leaving the others off.

I just finished with a full scan from the Microsoft Safety scanner and it didn't say there was anything wrong. I haven't reset the computer yet to see if anything has changed though after resetting to factory (see 2nd paragraph) it seems to have gone back to Yahoo (the search engine it kept changing back to).

I opened the History tab in the toolbar menu and everything seems fine there. I also had the Always use Private browsing mode off to begin with. After enabling Clear History When Firefox Closes option, I ended up having to reset to factory settings (the things it saves were saved so it's not much of an issue) which did seem to fix the problem with the History Sidebar not coming up.

Well, here's hoping.

https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

These can't get your data back, but will help in the future.

These add-ons can be a great help by backing up and restoring Firefox

FEBE (Firefox Environment Backup Extension) {web link} FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backup of files that you choose.

OPIE {web link} Import/Export extension preferences

Forgot to add; Please flag your last post as Solved Problem so other will know.

Alright, but I just restarted the computer and the issue with the search bar still persists.

https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save