从Access运行时，UPDATE查询工作正常，但从C＃app中引发SQL语法错误

I have a very simple Update statement that will update mail server settings and network credentials info... Query works fine when I run it in Access but C# keeps giving me the error stating that my SQL Syntax is wrong ... I have a dataaccess layer (dal class) and Update instance method pasted belows ... But the problem must be sth else cuz I have updated lots of stuff this way but this time it just won't do .. any clues will be greatly appreciated. Thx in advance.I have a very simple Update statement that will