VB6:Unable to unload within this context

I have a form with a label set up as an array – Label1(0). I have used the Load and Unload events to put additional values into the array thus:-
for f=1 to 10
Load .Label1(f)
….
Unload .Label1(f)
next
My problem is this:
The firsttime through the code, the program has no problem Loading and Unloading, but subsequently I recieve the following error message:-Unable to unload within this context (Error 365)
I have looked at the MSDN help files but to no avail.
If anyone couldhelp I would be grateful