I declared a temporary table

declare @TempMyPeriods table (Prod  varchar(50) NOT NULL)

and when I try to extract the data into a different table I get the error

Cannot resolve the collation conflict between "SQL_Latin1_General_CP1_CS_AS" and "SQL_Latin1_General_CP1_CI_AS"

The issue was that the temp tables Prod column by defautl is set up as “SQL_Latin1_General_CP1_CS_AS”

So the Fix:

declare @TempMyPeriods table (Prod  varchar(50) collate SQL_Latin1_General_CP1_CI_AS NOT NULL)