Check pwproxy.key file
cat /opt/pbxware/pw/etc/pwproxy/pwproxy.key
In case you see line between private key and certificate looking like this:
DyhcWQ8ntKN7RcEntIkqNWmpug==
-----END PRIVATE KEY----------BEGIN CERTIFICATE-----
MIIFKDCCBBCgAwIBAgIIbM0MABrxYS8wDQYJKoZIhvcNAQELBQAwgbQxCzAJBgNV
Make sure end of the key and begin certificate are both on separate lines looking like this:
DyhcWQ8ntKN7RcEntIkqNWmpug==
-----END PRIVATE KEY-----
-----BEGIN CERTIFICATE-----
MIIFKDCCBBCgAwIBAgIIbM0MABrxYS8wDQYJKoZIhvcNAQELBQAwgbQxCzAJBgNV
Save changes and issue should be fixed
/opt/pbxware/pw/etc/jabber/server.pem
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