The mysterious and sudden downfall of seemingly unrelated applications

I have a very strange problem, I think interprocess communications aren't working properly (not sure what method these programs are using in common, though):

(Note that all these problems started at a seemingly random time while I was using the computer - I didn't even need to restart to see all these programs complaining in strange ways)

Some services refuse to start.
Wlcomm.exe isn't running either (this message appears instantly after asking WLM to sign in, while it works fine in Pidgin).
iTunes can't run or communicate with ipodservice.
Com+ System Application service won't start:

---------------------------
Services
---------------------------
Could not start the COM+ System Application service on Local Computer.



Error 1067: The process terminated unexpectedly.


---------------------------
OK
---------------------------

Looking at the dependencies for any service also fails:

---------------------------
Service Dependencies
---------------------------
Interface: Class not registered


---------------------------
OK
---------------------------

Wlcomm.exe, under debugger, dies with error code 0x80070057 (though I'm not sure if this is just because it needs arguments).
Even QTTask won't run, and it dies without error code.

I'm not sure what else is and isn't broken, but if anyone can help with this problem I'd be really grateful.
[Just for fun, note that it's mostly the programs that have always seemed the most flashy and bloated in my mind (itunes, quicktime, wlm) that have died.]

You may benefit by reading this.

You may benefit by reading this.

Is that the right link? I don't see much relevance - it's just telling me about wlcomm (which I need for build 14 of WLM to work), not what any possible problem with it could be (which seems to be affecting a fair portion of other programs too).

Uninstall and reinstall Live Messenger. I had thought that you would see the implication.

I doubt that would have worked; if you read the first post, the problems went much deeper than simply Windows Live Messenger - it was affecting others too, and even preventing some almost-vital services from running. I eventually reinstalled SP3, but that just worsened the problem. System restore did nothing.

So now I've reinstalled Windows, and updated to SP2. Everything works fine now, though moving my profile folder was tedious at best (downloading chown for windows, running it and cacls, moving profiles, altering hundreds of .lnk files to point to the correct location instead of the location Windows modified them to point to for no apparent reason).

I don't know if it's worth upgrading to SP3, because I had previously encountered a problem with Minecraft Server, described here under the heading "[INFO] Player1 lost connection: End of stream" - and with a very vague condition, "Problem: You're running Windows XP Service Pack 3".

Unrelated:
It also solved this problem: http://www.bleepingcomputer.com/forums/topic244403.html/page__view__findpost__p__1356038

Edited by Score_Under, 12 December 2010 - 05:08 PM.

You probably had some sort of malware infection on your computer, and a reinstall fixed it. As such you should upgrade to SP3.

You probably had some sort of malware infection on your computer, and a reinstall fixed it. As such you should upgrade to SP3.

Not everything is a virus ;)

But still, are there any tangible advantages to SP3? (That is, any advantages that are not merely bugfix or security update.) If so, I may get it, but I'm still not convinced it's worth the incompatibility it causes.

Edited by Score_Under, 13 December 2010 - 05:06 PM.