Hi Prasad,
Are you restored the environment through UJBR?are you get this error in other environment try to narrow down the issue through create one new dimension add one member and try to save and process it Another way you check the log in BW go through Tcode SLG1 in
object tab, type UJ and subobject, type UJA and execute the window you can find the details log and affected the area.Possible reason of this problem is your existing BPC version and current BPC version conflicted.
Khokan