# FAQ / Troubleshooting Guide
# RPC Errors
# certificate signed by unknown authority
When authenticating and authorizing a user for the first time, you get the following in your Pomerium logs.
ERR http-error error="401 Unauthorized: ..... rpc error: code = DeadlineExceeded desc = latest connection error: connection error: desc = "transport: authentication handshake failed: x509: certificate signed by unknown authority...."
Why
This error means that the proxy is rejecting the authorize service's supplied certificate (used to establish a secure connection) because it doesn't know or trust the certificate authority that is associated with the supplied certificate. This can happen for a few reasons.
Solution
Ensure that the proxy service knows about, and trusts the certificate authority that signed the authorize service's certificate.
Add the certificate authority directly into pomerium using the certificate authority config setting.
Add the certificate authority to the system's underlying trust store.
Replace your system / docker image certificate bundle.
COPY --from=builder /etc/ssl/certs/your-cert-bundle.crt /etc/ssl/certs/ca-certificates.crt
Finally, ensure that you aren't being man-in-the-middle'd or that some eager router isn't injecting it's own certificate along the way. Use openssl to verify that your proxy service is getting the certificate you think its getting.
$openssl s_client -servername pomerium.io -connect pomerium.io:443 </dev/null | sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p'
# rpc error: code = DeadlineExceeded
When authenticating and authorizing a user for the first time, you get the following in your Pomerium logs.
{"level":"error",..."error":"rpc error: code = DeadlineExceeded desc = context deadline exceeded","http-message":"rpc error: code = DeadlineExceeded desc = context deadline exceeded","http-code":500,"message":"http-error"}
Why
The proxy service is not able to create a connection with the authorization service to validate a user.
Solution
Usually, this is the result of either a routing issue or a configuration error. Make sure that you are using the internally routable URL for authorize service. Many cloud loud balancers not not yet support gRPC transposing the ingress. So while your authenticate service url will probably look like https://authenticate.corp.example.com
, your authorizer service url will likely be more like https://pomerium-authorize-service.default.svc.cluster.local
or https://localhost:5443