Automation error Exception occurred

Hi,

I got this error the other day. It was not on my computer but a friends computer. THey got this error when they try to run a macro. If i run the macro i do NOT get the error.

I have NO idea why this is happening.

Another interesting thing is that if my friend goes to developer menu then visual basic and presses the Run , and Run Macro........macro actually runs to completion.

I have googled this but to be honest i am lost........any ideas would be greatly appreciated.

FYI: i can not post the code.