Hi
I have an application that using SQL Server as database, would like to enhance it to support localization/globalization.
I changed my data field which allow foreign character set to use NCHAR/NVARCHAR. I changed all my string function to support localization, ie. LEFT() -> LEFTC() and etc

I have a problem that, whenever I changed my OS regional setting and language to other country, such as Thai / Chinese, I will face some error. Sometime the error is very misleading. Sometime, it just throw C5 error. The line of code that hit this problem is vary even I follow the same steps.

May I know what is the possible issue?
Thank you