Updated... I have now added something to reproduce the problem. If you're going to close this again saying it's a duplicate, could you please at least point us in the direction of the duplicate entry so that we can follow it!
As reported in following forum entry:
I have an SSIS package which is predominantly made up of script tasks. Putting a break point into a script task and pressing F5 to debug has the following symptoms:
1. I get the message: "SQL Server Integration Services Script Task has encountered a problem and needs to close. We are sorry for the inconvenience." there is a debug button and a close button.
Clicking on Debug instead of close brings up the Visual Studio Just in time debugger dialog which says:
An unhandled exception ('System.Runtime.InteropServices.COMException') occured in DTAttach.exe 
It then gives me options to continue debugging in a new instance of Microsoft CLR debugger 2005 or a new instance of Visual Studio 2005. Choosing the CLT debugger brings up the dialog box saying:
"An unhandled exception of type 'System.Runtime.InteropServices.COMException' occurred in Microsoft.SqlServer.ScriptTask.dll
Additional information: File position not valid for new breakpoint."
2. Choosing close instead of Debug comes up with the message:
"Microsoft Visual Studio for Applications has lost the link to .
Your work will be exported to C:\document and settings\ghooton\personal when you quit the application"
3. Clicking OK continues executing the package but does not break at the break point set.