You probably need to use append #'Public Service'!D4 (add single quotes)
instead of #Public Service!D4. If you are just making changes to the cell
value then underlying link does not change...

The right way to insert hyperlink is given below;
"To link to a location in another workbook, choose Existing File or Web
Page. Once you have located the workbook you with to link to, select the
Bookmark button and in the list under Cell Reference, select the sheet you
wish to link to, and in the Type in the cell reference box, enter in the cell
reference number. Click OK. If you have given your cells a defined name, then
in the list under Defined Names, click the name of the range you wish to link
to and click OK. "

"Tesons" wrote:

I'm using a hyperlink in one workbook to go to another workbook in a specific
cell location. I receive message "Reference not valid".

I created this hyperlink by selecting Insert--Hyperlink and choose existing
file. I appended #Public Service!D4 to the file address so it will navigate
to the specific cell location (D4) in Sheet Public Service.

Any help would be appreciated. Thank you.