error message when using a userform
 

hi everybody,

sorry, my english isn't very good.
I have made a programme in excel whitch makes several calculation.
there is a userform with commandbuttons and comboboxes.I use this
userform just to navigate through the spreadsheets and to get
informations for the results of the calculations on the userform. The
whole file is about 4,5 MB.
When i fill in cells and click enter or when i click on the
commandbuttons, sometimes i get a message "the sources of the system
are not enough to show all of it" (exact translation of greec
message).Every change on the spreadsheets runs a macro that updates
the results on the userform. I click "ok" and i go on properly. Does
anyone knows why i get this message and how i can face the problem.