Can you post your code for the UDF so we can see what you are trying to do. I have had no issue changing multiple cells / worksheets / workbooks from a single UDF. But maybe we are not talking the same thing. Can you share with us what you are doing?
The Frog -- ---------------------------------------------------------------------------------- Some important links for excel users: 1. Follow us on TWITTER for tips tricks and links : http://twitter.com/exceldailytip 2. Join our LinkedIN group @ http://www.linkedin.com/groups?gid=1871310 3. Excel tutorials at http://www.excel-macros.blogspot.com 4. Learn VBA Macros at http://www.quickvba.blogspot.com 5. Excel Tips and Tricks at http://exceldailytip.blogspot.com To post to this group, send email to excel-macros@googlegroups.com <><><><><><><><><><><><><><><><><><><><><><> Like our page on facebook , Just follow below link http://www.facebook.com/discussexcel