After upgrading ProjectWise and changing servers it is impossible to open any document from the datasource. Last Error  pops up saying:
"Error checking out a file of document '<doc.name>'. Failed to connect to the remote server application ".
Possible cause :
This error usually means that client cannot connect to the storage area. You should open PW Admin tool and check your storage areas. Most likely you need to correct the location of the physical files.
Please check that Project Wise Integration Service is running or not. If it stop, please start service again and try to login to datasource.
Otherwise, if this does not help - please consult server (dmskrnl.log) log files or contact Support.