SSIS Script task Precompiling fails, even though code has no errors

Have you ever written a beautiful piece of VB.Net code in your Script Task, but it just refuses to precompile? It happened to me.

It happened after I installed a patch for .Net framework 2.0, and then those silly script tasks just won't precompile no matter what.

Turns out the framework patch updated something to do with VSA (Visual Studio for Applications) engine, the same thing SSIS uses for Script Tasks. This would only happen on installations of SQL Server 2005, SQL Server 2005 SP1.

Updating to SP2 fixes this.

See here for more details:
http://support.microsoft.com/kb/932557
http://support.microsoft.com/kb/931846

Hope this eases some pain.