In Excel's Help, you can find the topic:
Features that are unavailable in shared workbooks
This includes inserting or changing hyperlinks.
harpscardiff wrote:
Hi,
I'm trying to figure out why I cant insert hyperlinks when the
worksheet is protected and shared. But I can insert hyperlinks when I
protect the sheet.??? 
Any help is much appreciated.
Thanks
--
Debra Dalgleish
Excel FAQ, Tips & Book List
http://www.contextures.com/tiptech.html