Add me to the list. I'm on SQLserver 2008 (not R2 and recentlly upgraded from 2005) and my SQA jobs calling SSAS ran fine up until one fine day earlier this week. I'm on a cluster and I've re-hosted my instances during the week to apply Windows updates (but not to all servers and I've re-hosted the SSAS instance to servers that haven't been updated yet and it still fails); other than that no changes in the environment, yet this code now throws the exception error we're all dealing with. The ClearCache test works in my environment as does the cube processing directly from SSAS.
This code comes directly from the SSAS cube Process, Script option and thence into the SQA job:
<Process xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ddl2="http://schemas.microsoft.com/analysisservices/2003/engine/2" xmlns:ddl2_2="http://schemas.microsoft.com/analysisservices/2003/engine/2/2" xmlns:ddl100_100="http://schemas.microsoft.com/analysisservices/2008/engine/100/100">