The timeout period elapsed prior to completion of the operation

If you are getting this following error while processing the Data Package:

Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding

Please try the following.

1) In Analyzer's Web.config file (\program files\analyzer\web folder), add the following key in the <AppSettings> section:

<add key="DataPackageTransferTimeout" value="1200" />

    The value is in seconds so the example above is 20 minutes.

If this happens while processing cube in SQL Management Studio then please try this:
1) Go to SQL Management Studio
2) Select the Tools menu
3) Select Options...
4) Click the Designers
5) Change the "Transaction Timeout After" value from 30 to 1600 seconds.

6) Restart SQL server then try again.