Object reference not set to an instance of an object when processing dimens

Hello BPC forum,

I am trying to use BPC Server Admin to move an appset from a 5.1 MS system to a 7.0 MS system and am getting an error

"Object reference not set to an instance of an object"

I have moved other appsets in this manner successfully. Upon further investigation I do see this error on our 5.1 MS appset when I do a full process of all dimensions. There are no errors in the dimensions, but during the OLAP update stage I also get this error. Has anyone ever ran across this? Any advice on how to resolve this? (i'm entering an SAP OSS note in parallel).

Many thanks!

Kevin