Share via

Inaccessible emails

Nelson N. Mahlangu 0 Reputation points
2026-03-24T08:34:51.11+00:00

Cannot able to access emails through outlook and owa...ECP and exchange tool box as well.

below is the error: when connecting through owa and ecp

This page isn’t working right now

127.0.0.1 can't currently handle this request.

HTTP ERROR 503

The mail server can respond to ping and nslookup using both ip address and FQDN

Exchange | Exchange Server | Management
Exchange | Exchange Server | Management

The administration and maintenance of Microsoft Exchange Server to ensure secure, reliable, and efficient email and collaboration services across an organization.

Locked Question. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.

1 answer

Sort by: Most helpful
Most helpful Newest Oldest
  1. Q&A Assist
    2026-03-24T08:35:06.8733333+00:00
    AI generated content. This question contains an answer created with AI from Q&A Assist. Learn more

    HTTP 503 for OWA/ECP with the server otherwise reachable usually indicates that the Exchange web application on IIS is failing, not a basic network/DNS issue.

    Based on the provided context, there are two Exchange-side issues and resolutions to check first:

    1. If this started after installing a security update
      • Use elevated permissions to reinstall the security update on the server:
        1. Select Start, type cmd.
        2. Right‑click Command Prompt → Run as administrator.
        3. In the elevated window, run the .msp file for the Exchange security update (full path) and press Enter.
        4. After the update completes, restart the server.
        5. Test OWA and ECP again.
      • If the error persists:
        1. Open IIS Manager.
        2. Go to Exchange Back End website → ECP virtual directory.
        3. Open Application Settings → BinsearchFolder.
        4. Ensure the paths are the actual Exchange install paths, for example:
          • C:\Program Files\Microsoft\Exchange Server\V15\bin; C:\Program Files\Microsoft\Exchange Server\V15\bin\CmdletExtensionAgents; C:\Program Files\Microsoft\Exchange Server\V15\ClientAccess\Owa\bin (adjust drive/version if different in the environment).
        5. Open an elevated Exchange Management Shell in C:\Program Files\Microsoft\Exchange Server\V15\Bin and run:
          • ./UpdateCas.ps1
          • ./UpdateConfigFiles.ps1
        6. Open an elevated Command Prompt and run iisreset.
        7. Restart the server and test OWA/ECP again.
    2. If this is Exchange 2013 and you see OWA/ECP failures with server‑side errors
      • Install Exchange Server 2013 Cumulative Update 11 or later on the server. This update:
        • Fixes a known issue where OWA/ECP requests fail due to a GUID mismatch stored in cookies vs. Active Directory.
        • Enables periodic recycling of the OWA/ECP app pools (every 14 days) to prevent recurrence.
      • Do not disable this recycle or extend it beyond 28 days, or the issue may return.

    If the environment is Exchange 2019 and the 503 appears specifically during client‑side search via EWS (for example, Outlook search returning “We’re having trouble fetching results from server”), this is a known CU13 issue; use Outlook in Online mode or OWA search as a workaround and then follow the server‑side steps in the referenced article.

    References:

    0 comments