PL-900 Practice Question: Demonstrate the capabilities of Power Automate
A company has a Power Automate flow that uses a premium connector (e.g., SQL Server). Several users report that the flow fails with a '401 Unauthorized' error. The flow uses a service principal for authentication. What is the most likely cause?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The service principal's certificate has expired.
Service principal certificates have expiration dates. When the certificate expires, authentication fails with a '401 Unauthorized' error. Option A is incorrect because a wrong connection string would produce a different error (e.g., 'Cannot connect to SQL Server'). Option B is irrelevant as the environment does not affect authentication. Option C is incorrect because rate limits cause '429 Too Many Requests', not 401.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The SQL Server connection string is incorrect.
Why it's wrong here
Incorrect connection string would cause a different error.
- ✗
The flow is not in the default environment.
Why it's wrong here
Environment does not affect authentication.
- ✗
The flow is exceeding API rate limits.
Why it's wrong here
Rate limits cause 429 errors, not 401.
- ✓
The service principal's certificate has expired.
Why this is correct
Expired certificate causes 401 errors.
Go deeper
Related to this question
About these practice questions
Courseiva writes every PL-900 question from scratch — 904 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This PL-900 practice question is part of Courseiva's free Microsoft certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the PL-900 exam.