Nero 7 popup message

i have nero 7 on win xp. i just started making data dvds. however, whenever i click the “add” button to add files, a message window pops up. it says:

This action cannot be completed because the other program is busy. Choose Switch to, Retry or Cancel to activate the busy program and correct the problem.

the “Cancel” button is not highlighted to be used.
the “Retry” button attempts to retry but is unsuccessful every time.
the “Switch To” button just brings up the Windows XP Start Button on the taskbar

this is a very annoying problem and i’m stuck. anyone know what to do to fix this?

When the Windows start menu comes up after hitting “switch to”, have you tried hitting ESC?

just tried it. it didn’t do anything. any other suggestions