Unable to create any link/hyperlinks in a particular excel file
 

Please help me as I have an existing excel file where I have copied lots of
links and hyperlinks but it seems it is not working with that particular
excel file. I do have internet access and hyperlinks are working fine in
other files but problem is with a specific excel file. The hyperlink and link
promt are inactive in this file particularly and even when I am trying to
copy the content of these file to a new file the same problem is occuring.

But other links are working in new excel file.

Can you kindly help me ???