How do you copy an Integer field to a UD String field in the same table?

I did the change to the production database name to Epicor10 and it was then that I got the error mentioned in my last post.
If I add the servername ‘EpicSQL’ to it I get:

Msg 7202, Level 11, State 2, Line 1
Could not find server ‘EpicSQL’ in sys.servers. Verify that the correct server name was specified. If necessary, execute the stored procedure sp_addlinkedserver to add the server to sys.servers.

My complete query on the EPICSSRS server is:

select * from [dbo].[PORel_17682f6ecb1d4415949b65222f553af8] T3 left outer join EpicSQL.Epicor10.Erp.TranGLC T5 on T3.Company = T5.Company AND T5.key1 = cast(T3.PONum as varchar) and T5.key2 = cast(T3.POLine as varchar) and T5.key3 = cast(T3.PORElNUm as varchar) AND T5.RelatedToFile = 'PORel'