"Execute Package Utility has encountered a problem and needs to close"

I'm a SQL Server 2000 user trying to get my head around v2005, in particular the changes from DTS to Integration Services.

I've build a few packages in BIDS and they work fine there, but saving them to either the file system or MSDB locations and running them in Management Studio results in:

Execute Package Utility has encountered a problem and needs to close. We are sorry for the inconvenience.

If I click on the debug button, I get this:

An unhandled exception ('System.IO.FileNotFoundException') occurred in DTExecUI.exe [404].

I've searched the Internet and found a few people who has also experienced this, but not received any answers.

Is there a kind guru out there with some idea of what is going on? Preferably something that doesn't involve re-installing, because the database has already been configured for our Blackberry users and I can't re-do it now.
I have the same problem... have you got a soln yet?

Thanks|||I also get the same problem. Looking in the event log, it is appears it cant find a temp file...but that doesnt make sense to me. Any solutions?|||I had the same problem. It got fixed after applying SP2.