Type Mismatch when Using char(13) in VBScript in outlook Form

[Amir]

Type Mismatch when Using char(13) in VBScript in outlook Form.
Just having this line creates error:
a = char(13)

or ANY char does not work.
HOW to go around that?

I tried:
vbcrlf
System.Enviroment.NewLine
char(13) & char(10)

none worked

Please help.