I'm looking into making the switch from SourceSafe to SVN.

But, when I installed the 64-bit TortoiseSVN client version 1.5.5 on my Vista Ultimate x64 box, I got a BSOD upon the next reboot. The error was IRQL_NOT_LESS_OR_EQUAL.

I was able to boot by hitting F8 and going into the Last Known Good configuration. Once I got back to my desktop, I uninstalled the SVN client and rebooted again. This time, no crash. It was definitely the client, or something triggered by it.

I tried a re-install of the client, but this time with my antivirus disabled (Eset Nod32 64-bit) and everything else quit out of the notification area (ATI Catalyst stuff, SyncBack Pro, Daemon Tools, various Logitech stuff for my G15 and MX 1000, Window Clippings, HP Digital Imaging Monitor). The install went smoothly and I made it back into windows just fine, with the SVN client working, including shell integration.

My hunch is that some aggressive anti-virus protection was keeping the client from installing itself properly. Upon reboot, windows encountered some partially loaded software, couldn't make sense of it, and crashed. It's rare to see a BSOD that is not hardware or driver related, so I think some driver was getting confused somewhere.

2008-12-10 Update: Even after reinstalling Tortoise SVN with anti-virus disabled I was having BSODs on later reboots. I have now removed Eset Nod32 x64 Anti-virus, Daemon Tools, Adobe Version Cue Server, and Adobe Drive CS4 x64. Things seem to be working now. My new theory is that it was Adobe Drive CS4 x64. This app does version control and is a shell extension just like Tortoise SVN. I bet they were conflicting.

2008-12-10 Update 2: Successive reboots were OK, but when trying to run a disk check upon reboot, I was bluescreening. Thinking about this more carefully, I actually had it working earlier where it would boot up OK, but bluescreen during the disk check, if one was scheduled for the next bootup. I used SysInternals Autoruns app to search for stuff that is starting up with the system that may be conflicting. Doing a search for "Adobe" finds some stuff other than Adobe Reader / PDF-related stuff. Specifically I saw an Adobe Device Somethingerother (I should have written it down before deleting it, but I figured if I needed it back I'd reinstall CS4) and an Adobe File System driver. They both sound like they're related to the Versioning system or are otherwise related to hardware device management, which means they may mess with kernel-mode code, which can cause a BSOD. So, I removed both of those and I can now reboot and even run a disk check without problems. I THINK I've got it at this point but I'll let this configuration ride for a bit before I mark this as Solved.

2009-03-08 Update: No crashes in months, so this is a done deal! SOLVED!