What causes REST continuation token NULL error?

The backend service returned a JSON response with a null token value, indicating it cannot provide a valid continuation token for the next partition or page. The REST source is configured with pagination rules that expect a non-null token, but the service signals end-of-data or an error using a null token instead of an empty response. A partition boundary or query range returned no data, causing the service to emit a null token rather than omitting the token field entirely. Stale or expired session context caused the backend to reset pagination state and return a null token mid-traversal

How do I fix REST continuation token NULL error?

Step 1: Inspect the full JSON response body from the REST source (visible in pipeline diagnostic output) to confirm the token field is explicitly null versus absent, as these may require different handling in the pagination rule configuration.. Step 2: Update the pipeline's REST connector pagination settings to handle a null token as a stop condition — configure the 'AbsoluteUrl' or 'QueryParameters' pagination rule to exit the loop when the token value is null or empty.. Step 3: If the data source supports it, reduce the partition size or query range so that each page returns a valid non-null continuation token, avoiding edge cases at partition boundaries.. Step 4: Check whether the backend service has a known behavior of returning null tokens to signal the last page and update the pipeline's pagination exit condition to treat a null token as end-of-dataset rather than an error.. Step 5: Re-authenticate or refresh the connection to the REST source if session expiry may have caused the null token, then re-run the pipeline to verify the pagination resumes correctly from the start.

Medium severitydata formatMicrosoft Fabric →

Power BI Refresh Error:
REST continuation token NULL error

What does this error mean?

This error occurs when a Fabric pipeline REST connector receives a null continuation token from a backend service during paginated query execution across multiple partitions. The pagination loop cannot continue because the token needed to fetch the next page is missing.

Common causes

1The backend service returned a JSON response with a null token value, indicating it cannot provide a valid continuation token for the next partition or page
2The REST source is configured with pagination rules that expect a non-null token, but the service signals end-of-data or an error using a null token instead of an empty response
3A partition boundary or query range returned no data, causing the service to emit a null token rather than omitting the token field entirely
4Stale or expired session context caused the backend to reset pagination state and return a null token mid-traversal

How to fix it

1Step 1: Inspect the full JSON response body from the REST source (visible in pipeline diagnostic output) to confirm the token field is explicitly null versus absent, as these may require different handling in the pagination rule configuration.
2Step 2: Update the pipeline's REST connector pagination settings to handle a null token as a stop condition — configure the 'AbsoluteUrl' or 'QueryParameters' pagination rule to exit the loop when the token value is null or empty.
3Step 3: If the data source supports it, reduce the partition size or query range so that each page returns a valid non-null continuation token, avoiding edge cases at partition boundaries.
4Step 4: Check whether the backend service has a known behavior of returning null tokens to signal the last page and update the pipeline's pagination exit condition to treat a null token as end-of-dataset rather than an error.
5Step 5: Re-authenticate or refresh the connection to the REST source if session expiry may have caused the null token, then re-run the pipeline to verify the pagination resumes correctly from the start.

Frequently asked questions

Does a null continuation token always mean the data load was incomplete?

Not necessarily. Some REST APIs return a null token on the final page as their way of signaling end-of-data. If the null token appears on the last partition after all data was returned, the load is complete. The issue arises when the null token appears mid-traversal, before all partitions have been read — always cross-check row counts against the source to confirm completeness.

How do I configure the Fabric REST connector to stop pagination on a null token?

In the REST connector's pagination rules within the pipeline Copy activity source settings, set the pagination stop condition to check whether the next page token expression evaluates to null or empty. Using a rule like `@equals(activity('Copy').output.paginationNextLink, null)` as the exit condition will gracefully end the loop when a null token is received.