Psychic debugger says you either are passing to SP_ExecuteSQL
a variable of type varchar (make it nvarchar), or you've got a string you haven't used the unicode prefix on:
E.g.
Exec sp_executesql 'select * from something'
To fix it use:
Exec sp_executesql N'select * from something'
Notice the N
prefix on the string.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…