Hi,

Two codes were opened for same country so one needs to be deleted, can 't delete because it is used in some transactions. So is there any possible way to block one code.

Regards,
Alerts

You can delete any master data till it is NOT used in another master / transaction.
Since another country code is already used in transactions, one of the solutions is you can change the description (something like duplicate country / do not use, etc.). Send email to all the users not to use such kind of duplicate data. However when you take a printout wherever this code is used, the new description would get printed

You could use ttaad4229m000 to see where the old country code has been used and then amend those records using General Table Maintenance (at your own risk!). Then delete the incorrect country code. However, Print References to Parent doesn't pick up finance data so you would either have to accept those records would refer to the old country code or try to find those also.