This is a common error in SQL Server client/server connectivity, many varied factors may lead to the same error, eg the firewall setting in SQL Server Server, or incorrect information provided in Replicate Endpoint, etc. we found a few helpful links, please have a try:
If the problem persists, you may try to create an ODBC DSN and use the DSN to troubleshoot the connectivity issue, it's a bit easier than do that in Replicate.
Good Luck,
John.
Help users find answers! Do not forget to mark a solution that worked for you! If already marked, give it a thumbs up!
.png){kind=link}