This browser is no longer supported.
Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support.
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(128, 8%, 22%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EA%3C/text%3E%3C/svg%3E)
I want to set up a data validation rule that triggers if another cell is not empty.
For example:
If cell A1 has a value in it, and the user tries to enter a value in cell B1, I want an error message to pop up to say that they cannot enter a value in cell B1.
I have tried using A1>=0 and NOT(ISNULL,A1) and NOT(ISBLANK,A1) but none of these work.
Can anyone offer any suggestions?
Thanks
A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Answer accepted by question author
Hi,
While in cell B1, go to Data > Data Validation > Allow > Custom and in the formula box there, enter this
=A1=""
Click on OK.
Hope this helps.