On Friday 7/14/17 we unfortunately upgraded to Sage 2018.  We have state of the art hardware (Server/Clients).  Solid State drives in Server and Clients.  Under 2017 all queries to database via Sage50 were fast.  Selecting a Customer from Pull down in Customer Management was fast in 2017.  We upgraded Server and Clients to 2018.  Everything went smooth during migration.  After upgrade users started to complain that the Customer pull down was taking 15 minutes to populate under 2018.  In 2017 it loaded instantly.  Called support and there final answer after we exhausted all other possibilities was that we have to many Customers.  If we have to many Customers why did it work under 2017.  My belief is that the new version lookup code was changed and it is effecting lookups on large tables.  Sage needs to fix this issue asap because upgrading to a new version should improve the system not cause issues that were not present in 2017.  Our only option is to go back to Sage 2017 but that would be a monumental task.  I would not recommend upgrading to 2018 if you have large customer table or any other large tables.

As you can see below...when you select down arrow Sage50 2018 sits and spins for about 15 minutes until it finally populates.  In 2017 it loaded instantly.  Please fix your new 2018 code/query.