Question

After uploading .xls file to the server it becomes read only. How to make it back read/write.

Answer 1

You have to check what read only really means in this case – is it lack of write permission (then use chmod to set one after all) or maybe your file is owned by someone else (which often happens on incorrectly configured hostings, where uploads are handled by httpd, not the user owning file hierarchy. If you got shell access do this:

$ ls -l

to list the files and see who owns it, then check what is your ownder id:

$ id

if these do not match, then you may need to reconfigure your server