Bizarre IE7 crash on Vista

The only detail I had before arriving was ‘Internet Explorer won’t start up’. And so it proved. Double-clicking the icon produced a helpful Vista error message with no further details, and event viewer had the same info. The first port of call with IE problems is to disable third-party add-ons, and there’s a helpful “run without add-ons” shortcut hidden in the start menu. This crashed too. Hmph.

I reset the entire configuration from the ‘advanced’ tab of Internet Options and this fixed the problem. Once. After closing the browser it wouldn’t open again. On the basis that maybe the add-ons shortcut was lying, I tried disabling all non-MS add-ons. Nothing. Something was obviously getting its hooks into IE after the initial load, but I couldn’t find anything.

Much resetting later I found a fix: turn off ‘protected mode’. This was far from ideal, and not really addressing the issue. Vista’s IE7 ‘protected mode’ is designed to prevent IE from altering things it shouldn’t, and is a useful setting to enable on any machine which kids can access. Quick googling suggested some something must be trying to access a protected area on startup, killing IE in the process. I considered disabling the many MS ‘add-ons that run without requiring permission’, but they all looked necessary for IE to function at all.

I found another solution: disabling UAC. I haven’t used Vista much and UAC is already annoying the crap out of me, what with blanking out the screen for no apparent reason, supplying messages that I barely understand, let alone the average user, and generally whining about every other mouse click. I’d certainly disable it on my own PC, but I was reluctant to do so on someone else’s. Eventually I realised it only worked because turning off UAC automatically disables protected mode, so wasn’t helpful.

The machine is a couple of weeks old, and was working fine until yesterday, when Office 2007 and Norton 360 were installed. I suspect Norton, but then I’d probably suspect Norton if they’d only passed it on the shelf, such is my dislike of that program. I tried removing it, including running Symantec’s stand-alone uninstaller, but it made no difference.

I cleared out folders, ran the system file checker, scanned for spyware. Nothing helped. On XP I’d have reinstalled IE7, but there’s no way to do that on Vista short of reinstalling the entire OS. In the end I left it with protected mode disabled, but it’s niggling me. Even with the main shortcut working ‘no add-on’ mode still crashed, so it’s clearly still messed up under the surface. Annoying. Can anyone think of anything I missed, or a debugging technique I could have tried?