If you try to restore an SSAS 2008 .abf backup file to an SSAS 2005 instance, you will get the error
TITLE: Microsoft SQL Server Management Studio
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The following system error occurred: The file exists. . (Microsoft SQL Server 2005 Analysis Services)
BUTTONS:
OK
The solution:
1. Restore to SSAS 2008 instead. You’ve probably got the wrong version