First up, the Panel names are not stored in that array. The Panels themselves are the elements of that array, not their names.

Secondly, I'd suggest calling the GetUpperBound method of the array itself rather than the UBound function.

Finally, where exactly is that array declared? There are two possibilities from what you've posted. Either it's declared inside a method, in which case it doesn't exist in any other method, or it's declared at the class level, in which case all the elements will be null references.

That code will work as is, as long as you've created the array properly. You haven't provided enough content for us to know whether that's the case.