Some users get error while connecting to ssas 2012 using Excel 2010 :
Data could not be retrieved from the external data source.
Error message returned by the external data source:
memory error: allocation failure : not enough storage is available to process this command.
We fixed this error by installing correct version of Microsoft Analysis Services OLE DB Provider for Microsoft SQL Server (MSOLAP) in the client Excel. as mentioned in the previous blog.
While researching Internet I also came to know that in general the problem is with Excel when you are using 32bit Excel. For 32bit process, there is a limitation on the memory address space, the max it could go on is around 1GB. The best way is to avoid this error is using a 64bit of excel. More details at blog and in-depth information here.