Hi Glen,

Thanks for the reply. The application isn't able to control the forms due to the way it's designed, it's really an MDI application as many forms can be open at any one time.

To correct the issue in future versions of the application I'll change the form base class to include a Release command in the Unload method. My question was just to put my mind at rest as I ensured our customers that there wasn't a problem with the null variables.

Thanks again.

Andy