I am trying to prompt users with a message (when they click/use SAVE) to fill
in a cell with their LoginName.

This LoginName will be used as the filename to save the file automatically
in a SPECIFIC FOLDER.

This is what I'd like to achieve:

1. I have a Spreadsheet with 12 worksheets, January to December

2. The user enters his/her LoginName (JOHNDOE) in cell A1 in worksheet January

3. When user click/use SAVE; they will be asked to fill the cell A1 in
worksheet January if they have left this cell empty by mistake

4. When user click/use SAVE; they will get a prompt message asking them to
confirm whether their LoginName (johndoe) in cell A1 is correct

5. If they choose YES; the file will be saved in folder C:\timesheet\ as
johndoe.xls

6. The user will receive another prompt to let them know that the file was
saved as C:\timesheet\johndoe.xls

7. If they choose NO; sub ends and the user repeats the process with correct
LoginName

8. When user click/use SAVE AS (instead of using SAVE); they will be given
LoginName (johndoe) in the FILE NAME section of the SAVE AS prompt screen.

I have been working on this over a month and have tried everything I know.
I have also asked for help but owing to my limited knowledge - I'm back!

Please help and advice. Please be as detailed as you deem necessary - I'm a
novice.

Many thanks in advance.