In order to open a new case you must be designated as a Case Administrator. For more information on how to setup Case Administrators review https://www.veeam.com/kb2211.
Any information you can provide regarding the issue you are experiencing could have a significant impact on how fast the issue is diagnosed and resolved. You will be asked to provide the following information:
After you have created a case you will be contacted within the time set forth in the SLA agreement for the severity you specified.
Veeam's severity system operates similar to the DEFCON system, lower number=high priority.