Hi @HectorFlores ,
The key clue here is: "Refresh data" works fine, but "Refresh Schema & data" fails. That tells us the data connection is healthy — the problem is specifically in schema discovery against SAP BW.
The error Object reference not set to an instance of an object on schema refresh points to one of these causes:
Most likely — MDX/BEx query object no longer valid on BW side
The query or InfoProvider (sapuxbwp.ci.root/01/105) that the semantic model maps to may have been transported, modified, or re-activated on the SAP BW server recently. When schema refresh runs, Power BI re-interrogates the BW object's metadata and gets a null reference back because the object definition changed underneath it.
Ask your SAP BW team to:
Re-activate the BEx query or InfoProvider in BWTransaction: RSRT or RSA1Right-click query → Activate
Fix 1 — Republish the semantic model from Desktop
Since Desktop works fine, the safest immediate fix is to republish from Desktop to overwrite the Service model entirely. This re-registers the schema cleanly without relying on Service-side schema refresh.
Fix 2 — Check the SAP BW Gateway connector version
"Refresh Schema & data" uses a deeper metadata call than a normal refresh. Older SAP BW connector versions on the Gateway have a known bug where schema introspection returns a null object for certain BEx query structures. Go to your Gateway machine and update to the latest On-Premises Data Gateway release — SAP BW schema refresh fixes were specifically patched in 2024 and early 2025 builds.
Fix 3 — Avoid "Refresh Schema & data" entirely
In Power BI Service, schema refresh for SAP BW is generally unreliable and Microsoft themselves recommend managing schema changes through Desktop republish rather than Service-side schema refresh. Set your scheduled refresh to data only, and whenever the BW schema changes, re-publish from Desktop.
Fix 4 — Check for null-returning variables or restricted key figures
The path sapuxbwp.ci.root/01/105 suggests a specific node in the BW hierarchy. If that node contains a variable with no default value or a restricted key figure with an empty filter set, the schema introspection call returns null for that object — exactly this error. In RSRT, run the query with "No variable screen" and see if it executes cleanly.
Hope it resolve your problem
Thanks and Regards
GainInsights Solutions
Trusted Fabric Partner - https://gain-insights.com/partnerships/microsoft/
www.gain-insights.com
