Two of many models fail scheduled refresh, with gateway unreachable error, pass manual refresh

[PhilSmith]

I have two models that will not refresh on schedule.  Other models do.  These models refresh manually no problem.  I have moved schedules around, reduced the number of models refreshing at that same time, it is just these two models.  
"Gateway Unreachable" for different tables, the same tables used in other models that refresh just fine, at the same time.

Suddenly Power Bi Pro is not enough to get tech support from microsoft?  Since when?

Any ideas?

Phil

[Poojara_D12]

Hi @PhilSmith 

You're encountering a frustrating issue where two specific Power BI models fail to refresh on schedule, despite refreshing successfully when done manually. These models use the same tables as others that refresh without problems, and you've already tried logical steps like staggering refresh times and reducing concurrent loads. The error you're seeing, "Gateway Unreachable," typically suggests a problem with connectivity between the Power BI Service and the on-premises data gateway, but in this case, it's inconsistent since other datasets using the same tables and gateway work fine. This points more towards a potential gateway service glitch, network interruption, or resource contention affecting just these two models during scheduled runs.

As for Microsoft support, you're right to feel surprised—Power BI Pro users used to have access to standard support. However, in recent years, Microsoft has shifted its model, and now Pro users generally have access only to community support unless their organization has a paid support plan (like Premier, Unified, or Fabric support). Full technical support for troubleshooting gateway and refresh issues typically requires Power BI Premium or Fabric capacity or a paid support plan tied to your tenant. This change has led many organizations to reassess their support needs based on the criticality of their Power BI deployments.

[Nasif_Azam]

Hey @PhilSmith ,

You have two Power BI models that:

• Fail on scheduled refresh with “Gateway Unreachable” errors.

• Refresh manually without issues.

• Use the same tables as other models that refresh successfully.

• Other models using the same data and gateway are not affected.

You’ve already tried:

• Adjusting refresh schedules.

• Reducing concurrent refreshes.

1. Gateway Resource Bottlenecks

Even if other models work fine, if these two are larger or more complex, they may time out or fail to reach the gateway when multiple models are scheduled.

Suggestions:

• Temporarily isolate these models (no concurrent refreshes).

• Stagger refresh with at least a 15-20 min gap.

• Increase timeout or memory if you manage the gateway (especially for on-premises data gateway in personal mode).

2. Query Folding or Transformation Differences

Manual refreshes can sometimes succeed because of different execution paths compared to scheduled refreshes.

Suggestions:

• Check Power Query steps in these models.

• Ensure query folding is working where applicable (right-click steps → “View Native Query”).

3. Gateway Version & Service Account

Sometimes a stale gateway version or a service account authentication lapse causes odd issues.

Suggestions:

• Go to the Power BI Service → Manage Gateways.

• Ensure the gateway is updated.

• Re-authenticate the data source connections used by the failed datasets.

4. Dataset-Specific Issues

Some models might:

• Use different credentials.

• Call external APIs or have custom connectors with timeout issues.

Suggestions:

• Review dataset settings for those models.

• Run Fiddler or gateway logs for failed scheduled refresh attempts to inspect errors.

5. Advanced Diagnostics

• Go to the Power BI Admin Portal → Audit Logs to check gateway connectivity details.

• Check refresh history for detailed failure stack.

• Enable diagnostics logs on the gateway to trace what happens during scheduled refreshes.

 

If none of the above work:

1. Create a duplicate of the model, simplify the query, and test scheduled refresh.

2. Create a test Power BI workspace and isolate the model there to rule out workspace-level issues.

3. If you suspect gateway overload, consider running the gateway on a separate dedicated machine temporarily.

If you found this solution helpful, please consider accepting it and giving it a kudos (Like) it’s greatly appreciated and helps others find the solution more easily.

Best Regards,
Nasif Azam

[BhavinVyas3003]

The “Gateway Unreachable” error during scheduled refresh is often due to resource contention, network instability, or query complexity—especially when multiple models refresh at the same time.

• Update the on-premises gateway to the latest version.

• Reschedule the two failing models during off-peak hours (e.g., 2–4 AM) to reduce load.

• Review and simplify queries in those models if they are large or have merge/join operations.

• Verify credentials and data source mapping in Power BI Service > Dataset > Settings > Gateway connection.

• Check gateway logs (C:\Program Files\On-premises data gateway\logs) to confirm cause—look for timeouts or memory errors.

[PhilSmith]

I have isolated one, and it made no differnce.  There is one query that is as simple as it can be, consisting of about 15 unions.  This is handled in the MYSQL server.  I will try to cut this down and see if that gets me anywhere.  

The error log is not user friendly.  Any pointers or links to help me decode the error logs?

Thanx

[v-tejrama]

Hi @PhilSmith ,

Thanks for reaching out to the Microsoft fabric community forum.

I reproduced the issue by creating two PBIX files with slightly different datasets, published to the Power BI Service, both using the same on-premises data gateway.

Scheduled both to refresh at the same time. Manual refreshes worked fine, but scheduled refreshes sometimes failed with “Gateway Unreachable,” especially when I reduced system resources or disrupted the network.

Gateway logs (C:\Program Files\On-premises data gateway\logs) confirmed the failures.

It’s likely due to resource limits, network instability, or complex queries causing overload during scheduled refresh.

If the response has addressed your query, please Accept it as a solution and give a 'Kudos' so other members can easily find it.

Best Regards,
Tejaswi.
Community Support

[PhilSmith]

I don;t think resource limits, because I have far larger Models that work fine.  I don't think network instability, because all of my models use the same two sources, and only these two fail every single time.  I do have one query that is pretty complex, but if it refreshes manually, then it would refresh on a schedule if it is the only model in that time slot.  I will play with the query, try cutting it down some, to see what happens.

Thanx

[GilbertQ]

Hi @PhilSmith 

Could it possibly be the reason the schedule refresh is filing is that the refreshes are consuming too many resources on your gateway? What happens if you try refresh them one at a time? Does it refresh successfully? If it does, it potentially means you either need to refresh them 1 at a time or increase the hardware on your gateway.

[PhilSmith]

I put it in it's own timeslot yesterday.  Where I have as many as four similar models refreshing at the same time wth no problems, this one, all by itself, still failed to refresh, with teh same error.  I will keep it this way  until I get it fixed.  I expect tomorrow I will get the same error, but on a different table.