Fix Error “Too Many Transient Failure Retries Permanent Exception”

Introduction

If you’ve encountered the error “Too Many Transient Failure Retries Permanent Exception” while working with Exchange Online or Microsoft 365, you’re not alone. This error typically occurs during mailbox migrations, PowerShell operations, or synchronization tasks. It usually indicates that the system has exhausted its retry attempts due to repeated transient failures, resulting in a permanent exception.

In this blog post, we’ll explore the causes of this error and provide step-by-step solutions to resolve it.

Common Causes of the Error

The error “Too Many Transient Failure Retries Permanent Exception” can be caused by several factors, including:

1. Network connectivity issues between your on-premises environment and Exchange Online.
2. Throttling due to excessive requests or high resource usage.
3. Corrupted mailbox items or large attachments causing migration failures.
4. Misconfigured migration endpoints or incorrect credentials.
5. Service issues on the Microsoft 365 side.

Step 1. Check Network Connectivity

Before diving into complex troubleshooting, ensure that your network connectivity to Microsoft 365 is stable. Run the following PowerShell command to test connectivity to Exchange Online:

If the connection fails, check your firewall, proxy, or VPN settings to ensure that traffic to Microsoft 365 is not being blocked.

Step 2. Verify Throttling Policies

Throttling is a common cause of transient failures. To check if your account is being throttled, run the following command in Exchange Online PowerShell:

If you suspect throttling, reduce the number of concurrent operations or requests. For example, during mailbox migrations, limit the number of concurrent moves:

Replace <EndpointIdentity> with the identity of your migration endpoint.

Step 3. Identify and Resolve Corrupted Items

Corrupted mailbox items or large attachments can cause migration failures, leading to transient errors. To identify problematic items, use the New-MailboxRepairRequest cmdlet:

Replace <UserPrincipalName> with the affected user’s UPN. This command repairs common mailbox corruption issues.

If the issue persists, consider excluding corrupted items during migration. For example:

Step 4. Check Migration Endpoint Configuration

A misconfigured migration endpoint can also cause transient failures. Verify your migration endpoint settings using the following command:

Ensure that the endpoint credentials are correct and that the endpoint is properly configured. If necessary, recreate the endpoint:

Replace <AdminEmail> with the email address of an admin account with the necessary permissions.

Step 5. Monitor Service Health

Sometimes, the issue may be on Microsoft’s side. Check the Service Health Dashboard in the Microsoft 365 admin center to see if there are any ongoing incidents or advisories. If there are, you may need to wait for Microsoft to resolve the issue.

Step 6. Increase Retry Limits

If the error persists, you can increase the retry limits for your migration batch. Use the following command to modify the retry settings:

Replace <BatchIdentity> with the identity of your migration batch. This command increases the retry count to 20 and sets a retry delay of 30 minutes.

Step 7. Restart the Migration Batch

If all else fails, restart the migration batch to reset the retry counter:

Troubleshooting Tips

• Check Logs: Use the Get-MigrationUserStatistics cmdlet to review detailed logs for the affected user:
  
• Test Connectivity: Use the Test-MigrationServerAvailability cmdlet to test connectivity to your on-premises environment:
  
• Contact Support: If the issue persists, consider opening a support case with Microsoft.

Conclusion

The error “Too Many Transient Failure Retries Permanent Exception” can be frustrating, but it’s usually resolvable with the right troubleshooting steps. By checking network connectivity, verifying throttling policies, resolving corrupted items, and ensuring proper migration endpoint configuration, you can overcome this error and complete your tasks successfully.

If you have any questions or additional tips, feel free to share them in the comments below. Happy troubleshooting!