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On this page
  • You are experiencing one of the following issues
  • Unblock yourself
  • Self-signed certificate in certificate chain
  • OPENSSL_internal error
  • Still Need Help?
Resolve issuesPostman app

I am having trouble adding client certificates

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No requests captured error while capturing Proxy

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I am seeing the error Request not found or Collection not found

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You are experiencing one of the following issues

  • I am getting self signed certificate in certificate chain error
  • I am getting OPENSSL_internal error

Unblock yourself

Self-signed certificate in certificate chain

  • If you are using a corporate firewall and/or VPN, try disabling them or using a different network. If you’re not able to replicate the error, it is likely that the VPN or proxy installed on your computer is preventing your request from connecting to the API service.

  • If you are using a self-signed certificate, make sure to add the correct client certificate files (CRT, KEY, or PFX) from Settings > Certificates > Client Certificates > Add Certificate.

  • Note: You can check for certificate data being used from the Network response pop-up or the console as explained here .

OPENSSL_internal error

**Why?**This error is usually a result of a handshake failure due to incorrect certificate files being used, which means that the server and browser were unable to establish a secure connection.

  • Go to Settings > Certificates and add the correct client certificate file (PEM for CA certificates, CRT, KEY, or PFX for self-signed certificates). You can check for certificate data being used from the Network response pop-up or the console as explained here .
  • Another potential workaround is to use the Newman CLI tool to send a request.
    • See our GitHub repo for various options, including the ones to add client certificates .

Still Need Help?

Submit a support request with the result of each of the following steps in the ticket:

  • Whether or not the issue persists when sending a request after toggling off Enable SSL certificate verification in the Settings tab of your request.
  • Open your terminal, copy and paste each of the following commands in turn (Replace postman-echo.com  with your API endpoint). Then share the verbose log (make sure to remove any sensitive details) for each.
    • curl -v -k https://postman-echo.com
    • openssl s_client -state -connect postman-echo.com:443 | openssl x509 -text

Have more questions? Submit a request