Regardless of what is causing the issue have you considered not updating the table, but rather do the insert into a new table where you add the column on the...

Just as an alternative - and I hope no smart (....) copies this to another site.

select *
, stuff(upper(a.Month_Name), 2, 10, lower(substring(a.Month_Name, 2, 10)))
from...

Hi,

Just curious about this - cut and past from a sqlservercentral https://www.sqlservercentral.com/Forums/1998921/Initcap-the-characters-in-SQL-server post onto social.msdn

https://social.msdn.microsoft.com/Forums/sqlserver/en-US/5cb9c231-dad7-4195-9f83-29ec709d5f70/how-to-initcap-the-characters-in-sql-server-in-sql-query-without-creating-any-function?forum=sqldatabaseengine#71813bb7-be29-443b-9c57-5cfe2d3590d8
Would normally consider this to be bad ethics but maybe its...