We have been hearing that customers installing SQL Server 2008 and SQL Server 2008 August CTP are hitting the following error:
“Invoke or BeginInvoke cannot be called on a control until the window handle
has been created.”
This issue is occurring due to .NET behavior on Win7 change that is exposing a bug in how we close UI dialogs. Generally, if you just rerun it won't hit the issue again.
This issue will be addressed in SQL Server 2008 R2 and a future SQL Server 2008 CU.