>Hi,
>
>My application when exiting from a modal form called from a class, will
>give runtime error '5', invalid procedure called or arugment.
>
>However, this error does not happen when debugging it in the IDE.
>I am loss, please help and advise.
>
>I am using VB 6.0 Entreprise (SP5) with Windows 2000 Professional with service pack 2

Can you reproduce the error with a small number of lines (that you can paste here) ? Very often, adding some DoEvents will help in that kind of bug which works in IDE but not in full speed.