Data Validation

To best describe or illustrate your problem you would be better off attaching a dummy workbook, the workbook should contain the same structure and some dummy data of the same type as the type you have in your real workbook - so, if a cell contains numbers & letters in this format abc-123 then that should be reflected in the dummy workbook.

If needed supply a before and after sheet in the workbook so the person helping you can see what you are trying to achieve.

Doing this will ensure you get the result you need!

To attach a file to your post, you need to be using the main 'New Post' or 'New Thread' page and not 'Quick Reply'.
To use the main 'New Post' page, click the 'Post Reply' button in the relevant thread.

On this page, below the message box, you will find a button labelled 'Manage Attachments'.
Clicking this button will open a new window for uploading attachments.

You can upload an attachment either from your computer or from another URL by using the appropriate box on this page.
Alternatively you can click the Attachment Icon to open this page.

To upload a file from your computer, click the 'Browse' button and locate the file.

To upload a file from another URL, enter the full URL for the file in the second box on this page.
Once you have completed one of the boxes, click 'Upload'.

Once the upload is completed the file name will appear below the input boxes in this window.
You can then close the window to return to the new post screen.