Occasionally upgraders may see this error in the event log when upgrading from A2E Standard to Add2Exchange Enterprise:

20110527120358: Failure updating [Table] A2E_Relationships Error is: 0 Meaning: Please contact tech support. | Calling program: Add2Exchange Console
For further information/support, please visit:
http://support.diditbetter.com/SearchResults.aspx?q=20110527120358: Failure updating [Table] A2E_Relationships Error is: 0 Meaning: Please contact tech support. | Calling program: Add2Exchange Console 

This is an error which can safely be ignored if after full replication there are no errors in the Event viewer.  The system was automatically updating tables, and did not do it fast enough for the system to return a proper result, so it tried again. Occasionally it may take a few times to update it correctly, and will show a few of these errors until it is successful.  If it is unsuccessful, the Console will not open and you will be directed by a prompt to contact technical support. 
 

Before opening the A2E Console, please be sure the A2ESQLServer service is on and started with the Add2Exchange Service Account.  If it is not, start the service, and then try to open the Console again.