The expired certificate does now show an error when trying to connect using it. There may be other ways to induce this similar issue, where the SASL fail generates a cryptic error message that doesn't mention SASL.
* Connecting to irc.libera.chat (+6697)
* [10101] Host disconnected
* Disconnected
* Connect retry #1 irc.libera.chat (+6697) (dns pool)
* [10101] Host disconnected
* Disconnected
* Connect retry #2 irc.libera.chat (+6697) (dns pool)
* [10101] Host disconnected
* Disconnected
In this case, I created it by using an RSA 'e' that OpenSSL doesn't support, but I don't know whether the error is happening in the OpenSSL routines used by mIRC or by the server. NIST's FIPS rules allows 'e' to be up to 2^256-1, but OpenSSL limits it to 2^64-1.
The certificates below have identical 'n' and primes. But the 1st one works because e=2^64-59, while the 2nd fails due to e=2^64+13.
If mIRC is asking an OpenSSL subroutine to check the certificate when installing it in the menu, there might be a problem with getting a false 'ok'. For the 2nd certificate that fails:
openssl verify -CAfile certfile certfile
result: OK
openssl verify -check_ss_sig -CAfile certfile certfile
result: lots of cryptic error messages
* * *
This cert using e=2^64-59 works
-----BEGIN PRIVATE KEY-----
MIIJRgIBADANBgkqhkiG9w0BAQEFAASCCTAwggksAgEAAoICAQDP7776Zquiif77
752j6ei366x762GKz6R7L7776Zquiif77752j6ei366x762GKz6R7L7776Zquiif
77752j6ei366x762GKz6R7L7776Zquiif77752j6ei366x762GKz6R7L7776Zqui
if77752j6ei366x762GKz6R7L7776Zquiif77752j6ei366x762GKz6R7L7776Zq
uiif77752j6ei366x762GKz6R7L7776Zquiif77752j6ei366x762GKz6R7L7776
Zquiif77752j6ei366x762GKz6R7L7776Zquiif77752j6ei366x762GKz6R7L77
76ZquikcyFVDzI6GJojnyltr+3BAdh7U91374rhk2eQKOoTvQ+zYynwi20B2LSsw
fzAtGt2WvrpFVDzI6GJojnyltr+3BAdh7U91374rhk2eQKOoTvQ+zYynwi20B2LS
swfzAtGt2WvrpFVDzI6GJojnyltr+3BAdh7U91374rhk2eQKOoTvQ+zYynwi20B2
LSswfzAtGt2WvrpFVDzI6GJojnyltr+3BAdh7U91374rhk2eQKOoTvQ+zYynwi20
B2LSswfzAtGt2WvrpFVDzI6GJojnyltr+3BAdh7U91374rhk2eQKOoTvQ+zYynwi
20B2LSswfzAtGt2WvrpFVDzI6GIWbQII/////////8UCggIALoiE1oMbBfL7Fbhd
v4uFvLTBV6UssiV1SFfDUOez0MDeiIARHJJhDjzQg1m92oeT4o1n77/H09AbYC4y
4eZWCLr4EbewtkyoRqYR3r39VRsz2UM9kB3/WTzBtOAtbFtzlWKXnJwI+ky5Zz2r
lSydNwvx82IhIkW3SxYPPWt2UNjzRDxaEsENtjH+g7WtfZElo9GmvXsStKsr5iiQ
JomVIfaQa6SvIVx0c8F0I9as19qnQBcuDPqnK0cna+as+jbv6JfAvpuSm26q4BU5
iRZmIHySbJO+5mA8j8kNl1IPzb2zlbyFGF2dBt/uKM3iLiPwm0uPkUnuJvLsqxTm
np3e4U5cmcT67PgP1d7Svb/MRa4HX5JZWf0LduawhF3X4KrRvzifKiB0Gr8xAMK3
81nOAbf7h4wuHLZ/EUplxMYcwjqcoUSpsoMiEd7eDbjAmoMOw9ZyNjwyLzLo7kHB
H7hqNe3/9GzB8gERm5f6MzoolvoLILGLbFtpxnmFRlWi2ybYkL2gURKffUkIcFrO
PtXiTYmI3vVJ8k73HMd8Ml0AqRkgrJE76vdI1GokCJTaOGWQ1/bqtPRICjpb4uN6
zomcs1TT54ywhAfG/l0BLkkS7WQBxzDZ8WRzEWmGaCOegbitG8AaxI5QJG+Cz4r5
iOCEpznXgBovr/9Y+9GeczmpcVcCggEBAO/tPtInslkVYUoUetDS0XHBKXtKq6Aq
qhf8A8A07Y5QpEoUoLAvmgqzU2rZeXNs+W1MPtPtInslkVYUoUetDS0XHBKXtKq6
Aqqhf8A8A07Y5QpEoUoLAvmgqzU2rZeXNs+W1MPtPtInslkVYUoUetDS0XHBKXtK
q6Aqqhf8A8A07Y5QpEoUoLAvmgqzU2rZeXNs+W1MPtPtInslkVYUoUetDS0XHBKX
tKq6Aqqhf8A8A07Y5QpEoUoLAvmgqzU2rZeXNs+W1MPtPtInslkVYUoUetDS0XHB
KXtKq6Aqqhf8A8A07Y5QpEoUoLAvmgqzU2rZeXNs+W1MPtPtInslkPcCggEBAN3d
3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d
3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d
3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d
3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d
3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d
3d3d3d3d3d3d3d3d3rsCggEAUVXo6aCv2mPSpO6xneMp7FbLoaMHnWKN64fQktjP
qaADNkt46AokvkFMETDmcVta7gr6DvUbv5kk/R72iv5+CNUCz1vz4VA0qQRzyjTu
9MIisl4tzSFrnszz8RkL6o9HdFao9fuslTLqPXgI2Qc8UVf/lNTNSZpjiqBi9emG
lQh86blnuz355PfqmGvv9OsxPfSiwdB1/jJDEybzgK8Zow6/t21VB3J/oHNxw/dg
/Gn8E9dYrwjAByeVgj4vQMxrVjayjQIHTPl8KuGZvDYVV967k8o1YbYI8+6z3Qaa
3qnIA4t6eJwMClJyFWfY1EoprJ5bCdxu+R3MSNRBfzeyMwKCAQAAxqrMw/ru2JQv
w5eRO3JQjWh6VN8Zvvb9epf10VVpUtGnbA2lFax8t/xNi3JlJyTNjEWJw7Zr4cW6
bSaBcUNu+F2ORjuA8Pmj9jCWHR3v7zAjmP8cTLKGfpqpMewTi2WUC2TnzueGz4UG
p9MVwng6Du8UDGo4G8fXgAVC4VTNdRDnnNBU8cBhS8eKafodvNLdY0zTC0Dq/2xJ
Gwn+XI9EWz+htAW7ayduEKrjuJgYfMQ9yOHxdAsnoKOyeQwk+IhsIIhMMuut11Hl
z/Yit3cGRl1UIGau1Nid6MneELF0UssM7JQ/TDV7MmDskPz2ucsCvOvQs0M4MAfw
v3+25Fl5AoIBABH6XIEXZqU+Pgjp4tK7Jxy/D073FtY6qY+ZxKGeppfaUQUjCNXw
TeU7LNoaGOPcquRkDStasxM9jLzXRkfGW88NGvD3Q6c4hVSROTDK2354bxZmG7t5
tQSieGnc9eDno1Hy1OaVC/aYL2WmtSFrbHcQVhZPXqpRj6tle1b2PbhtkmcOOwUk
tlfNKyMo5gJdWS0FUOf8QSuDuIhJLxIB6eJdrXIWhO9lQhNj8eGdH6FahMHbs7Gt
qn61iYnWDJaOflqBQhYVYMYnZVFUspTbOPxmrI5ZWz7E+0V8+ainegBUDThgBfpJ
sP5VUTqm1TgdKOqiV7Ltr23rDOFneCpAt2A=
-----END PRIVATE KEY-----
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
* * *
This cert using e=2^64+13 fails
-----BEGIN PRIVATE KEY-----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-----END PRIVATE KEY-----
-----BEGIN CERTIFICATE-----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o8bMAxag8miCw1vfN+OZY2Xsji8vXYfyNPtE/xQEhBNIZdmRXYNaXNQmia+WW8kA
TQJCtWiChnTQsDdui0N6unR0UDFxl9Y70GzVIOcBPh+sNsTRhf3taCUgQrCwg0ub
P2ucWf/ANHKNKJApW2H/QKkdqSN1al/KKxvrIn1kuvvI1VVfu2z3K4d0mEaEgd4t
iLE6wD6BrPZN/fmGXIlCB0iziIz6NS/eUM+dmvLT28ZoynMoUKFZSWH6xLphp/ba
zHFU9r37p5qMIBVDLcCweG8bztDLtDwg0giq7vAjRmPrWesULxMOixiQO1Iucm+/
I9uRMJe4uJPXtTU+MpvxbJulBLx0RIdjnSOLdKC7/of9ONO3z/ZOTITcWY+Rjvef
gMFnb9E9R52WpdGfRm4kYeGK2kYhc0yEgwYXMBvbbvNcbfDOyiH/tPzoGmAqX//l
b2CD0gXmMPMhR93vXkEkV1G+uksBOhw7y6p/UKCts5moOG3IR5O1bbORbNiLwbWM
bZqloCzyPkoR
-----END CERTIFICATE-----
