My validation message doesn't appear when invalid data is entered.
Messages appear only when data is typed directly into the cells. Your message won't appear:
To identify cells that contain invalid data regardless of how the data was entered, point to Formula Auditing on the Tools menu, click Show Formula Auditing Toolbar, and then click Circle Invalid Data .
Notes
My data validation doesn't work.
Is validation applied to the cells? Find the cells on the worksheet that have data validation: click Go To on the Edit menu, click Special, click Data validation, and then click All.
Are users entering data by typing? Make sure users click each cell and then type the data. If users copy or fill data in validated cells, validation messages don't appear, and entry of invalid data isn't prevented.
Is manual recalculation turned on? If so, uncalculated cells may prevent data from being validated properly. To turn off manual recalculation, click Options on the Tools menu, click the Calculation tab, and then click Automatic under Calculation.
Are formulas error free? Make sure formulas in validated cells don't result in errors, such as #REF! or #DIV/0!. Microsoft Excel ignores the data validation until you correct the error.
Are cells referenced in formulas correct? If a referenced cell changes so that a formula in a validated cell calculates an invalid result, the validation message for the cell won't appear.
Are the referenced cells on the same worksheet or a different workbook? Cell references have to be to cells on the same worksheet. If you have to refer to a different worksheet or a different workbook, use a defined name and make sure the workbook is already open.
Copying, filling, and calculating by formula override my data validation.
Data validation is designed to display messages and prevent invalid entries only when users type data directly in a cell. When data is copied, filled, or calculated by a formula, the messages don't appear.
Note You cannot override data validation for lists that are linked to a SharePoint site.
Try the following:
Protect worksheet elements
Protect worksheet elements from all users
Switch to the worksheet you want to protect.
Unlock any cells you want users to be able to change: select each cell or range, click Cells on the Format menu, click the Protection tab, and then clear the Locked check box.
Hide any formulas that you don't want to be visible: select the cells with the formulas, click Cells on the Format menu, click the Protection tab, and then select the Hidden check box.
Unlock any graphic objects you want users to be able to change.
You don't need to unlock buttons or controls for users to be able to click and use them. You can unlock embedded charts, text boxes, and other objects created with the drawing tools that you want users to be able to modify. To see which elements on a worksheet are graphic objects, click Go To on the Edit menu, click Special, and then click Objects.
On the Tools menu, point to Protection, and then click Protect Sheet.
Type a password for the sheet.
Note The password is optional; however, if you don't supply a password, any user will be able to unprotect the sheet and change the protected elements. Make sure you choose a password you can remember, because if you lose the password, you cannot gain access to the protected elements on the worksheet.
In the Allow all users of this worksheet to list, select the elements that you want users to be able to change.
Click OK, and if prompted retype the password.
Give specific users access to protected ranges
You must have Windows 2000 to give specific users access to ranges.
On the Tools menu, point to Protection, and then click Allow Users to Edit Ranges. (This command is available only when the worksheet is not protected.)
Click New.
In the Title box, type a title for the range you're granting access to.
In the Refers to cells box, type an equal sign (=), and then type a reference or select the range.
In the Range password box, type a password to access the range.
The password is optional; if you don't supply a password, any user will be able to edit the cells.
Click Permissions, and then click Add.
Locate and select the users to whom you want to grant access. If you want to select multiple users, hold down CTRL while you click the names.
Click OK twice, and if prompted retype the password.
Repeat the previous steps for each range for which you're granting access.
To retain a separate record of the ranges and users, select the Paste permissions information into a new workbook check box.
Protect the worksheet: On the Tools menu, point to Protection, click Protect Sheet, make sure the Protect worksheet and contents of locked cells check box is selected, type a password for the worksheet, click OK, and retype the password to confirm.
Note A sheet password is required to prevent other users from being able to edit your designated ranges. Make sure you choose a password you can remember, because if you lose the password, you cannot gain access to the protected elements on the worksheet.
Help protect workbook elements and files
On the Tools menu, point to Protection, and then click Protect Workbook.
Do one or more of the following:
To protect the structure of a workbook so that worksheets in the workbook can't be moved, deleted, hidden, unhidden, or renamed, and new worksheets can't be inserted, select the Structure check box.
To use windows of the same size and position each time the workbook is opened, select the Windows check box.
To prevent others from removing workbook protection, type a password, click OK, and then retype the password to confirm it.
If the workbook is already shared, and you want to assign a password to protect the sharing, unshare the workbook.
Note You may also want to save or print the current version of the workbook, because this history might not apply to later versions. For example, cell locations, including row numbers, in the copied history may no longer be current.
If this check box is not available, you must unprotect the workbook before clearing the check box.
Set other types of protection if you want: Give specific users access to ranges, protect worksheets, protect workbook elements, and set passwords for viewing and editing.
On the Tools menu, point to Protection, and then click Protect Shared Workbook or Protect and Share Workbook.
Select the Sharing with track changes check box.
If you want to require other users to supply a password to turn off the change history or remove the workbook from shared use, type the password in the Password box, and then retype the password when prompted.
If prompted, save the workbook.
Protect a workbook file from viewing or editing
On the File menu, click Save As.
On the Tools menu, click General Options.
Do either or both of the following:
If you want users to enter a password before they can view the workbook, type a password in the Password to open box, and then click OK.
If you want users to enter a password before they can save changes to the workbook, type a password in the Password to modify box, and then click OK.
When prompted, retype your passwords to confirm them.
Click Save.
If prompted, click Yes to replace the existing workbook.
The Validation command is unavailable.
The list may be linked to a SharePoint site You cannot add data validation to a list that is linked to a SharePoint site. To add data validation, you must unlink the list or convert the list to a range.
You may be currently entering data The Validation command is not available on the Data menu while you are entering data in a cell. To finish entering, press ENTER or ESC.
The worksheet might be protected To remove the protection, point to Protection on the Tools menu and then click Unprotect Sheet.
The workbook might be shared In a shared workbook, Microsoft Excel can validate data, but you can't change the settings. To make the Validation command available, stop sharing the workbook.
Note You may also want to save or print the current version of the workbook, because this history might not apply to later versions. For example, cell locations, including row numbers, in the copied history may no longer be current.
If this check box is not available, you must unprotect the workbook before clearing the check box.