Find your symptom in the table, and follow the fix. Longer answers are below the table.
| Symptom | Likely cause | Fix |
|---|---|---|
| Nothing happens when I break the rule | The validation is not active for this user | Check the points in I do not get a warning or error |
| A user gets an error that the extension cannot be used | The user has no 2C FIELDVAL USE permission set |
Assign Use Field Validation (2C FIELDVAL USE). See Users cannot use Field Validation |
| The rule on one field also fires when I change another field | All lines of the validation run on every modification | This is how it works. Use Conditions to limit when the rules run |
| A rule on the Email field never fires | Business Central validates the Email field itself, before Field Validation runs | Use a field that Business Central does not check, such as Phone No. See Regular expressions |
| The line rules do not run when I release a document | Execute validation on Related Table modifications is off | Turn it on, on the condition with the table relation. See Table relations |
| The results page opens, and then the card says Not saved | The validation has the type Error: the change is reversed | Correct the data. Use the type Warning if users must be able to continue |
| I cannot choose Action after Validation | Actions only exist for the type Warning | Change the type to Warning. Changing back to Error deletes the actions |
| A regular expression accepts values that are wrong | The pattern matches anywhere in the value | Add ^ at the start and $ at the end. See the cookbook traps |
| A regular expression accepts an empty field | Patterns with * match an empty value |
Add a Mandatory rule, or use + instead of * |
| The Length rule refuses my Validation Value | The format is not min(0)..max(10) |
Enter both numbers in that exact format. See The Length format |
| Check Table shows nothing | The validation is not active, or no record breaks it | Check the Starting Date. It must be today or earlier |
| A corrected record is still in the Check Table list | The overview is not recalculated | Choose Calculate, or turn on Refresh Check after opening related page on the setup page |
| The message does not say which record is meant | The sample message only names the field | Add fields with Reference Fields for Notifications. See Notification and reference fields |
| Business Central asks "Your change might update related records" | You entered a table relation | Choose Yes |
| My unfinished validation from the wizard is gone | Closing the wizard before Finish deletes the unfinished validation | Run the wizard again and finish it |
| I cannot turn on Validate Default Dimensions | The table does not allow default dimensions | Default dimension validation is not available for that table |
The calculated filter CURRENTPERIOD does not filter on this month |
It is the accounting period | See Calculated validations |
Check these points in this order:
2C FIELDVAL USE.See also When a validation is active.
The users probably do not have the required permission set. Assign 2C FIELDVAL USE to every user the validations apply to, and 2C FIELDVAL MANAGE to the users who create and change validations. See Assign the permission sets. Add the permission set to every newly created user, or the extension gives an error.
With a Warning, the user is informed and can continue. The change is saved. With an Error, the change is reversed and the user cannot save the record until the data is correct. See Warning or error.
Use Check Table on the validation. It lists every existing record that breaks an active rule, and lets you open the record to correct it. See Check Table.
Field Validation checks a record when it is modified (and when it is inserted, with Insert Check on). It does this whenever the session has a user interface (the AL setting GuiAllowed), for example edits in Excel, configuration packages and imports started in the client. Writes without a user interface, such as API pages, job queues and background sessions, are not checked. Test your import in a test company with a Warning first.
For the length of the trial, how to turn a trial into a license and what to do in a new environment, see Licenses. In short:
Last reviewed: October 2026.