Error "No clean data columns available for custom fields" or "Unable to Access Page" When Creating a Custom Field in Salesforce

Why This Error Occurs: Custom Field Hard Delete Queue

When creating a custom field in Salesforce, the following error messages may appear:

• "No clean data columns available for custom fields"
• "Unable to Access Page"

These errors occur because of how Salesforce manages deleted custom field data internally. Custom field definitions are stored in a predefined column space for each object. When you delete a custom field, the column space used by that field is not released immediately. The deleted field data remains in the system until Salesforce runs a background hard delete process (also called a physical delete). A hard delete is a server-side cleanup job that Salesforce executes automatically during periods of low server resource usage.
During the time between when you delete a custom field and when the hard delete runs, the column space for that field appears occupied to Salesforce. If you try to create new custom fields before the hard delete completes, Salesforce reports that no column space is available, even if your active field count is below the object's limit.
Example scenario: Assume the maximum number of custom fields for an object is 100. You currently have 95 active custom fields. You delete 10 custom fields, bringing the active count to 85. You then immediately try to create 15 new custom fields. Salesforce reports an error because the 10 deleted fields have not yet been hard deleted, so their column space is still counted as occupied. After the hard delete runs — typically within a few days — the column space is released and you can create the 15 new fields.
Note: Salesforce currently has no means to confirm or trigger hard delete execution from within the Salesforce UI.