Wierd problem.

I have two workbooks. For some reason, when I attempt to select the
entire sheet1 in workbookA, I cannot paste it into workbookB with the
right click. The right click Paste is completely greyed out.
However, the item appears in the clipboard pane and I can manually
paste it if I click in the clipboard.

I've told my client to just use the clipboard, but he really wants to
simply use the right click paste option.

What would cause the right click paste and paste options to grey out
even though the task pane for the clipboard shows the item to be
pasted?

Thanks in advance.

Sparky