Possible Cause of error ?

[Patrice Guérin]

Hello,

Can anybody tell me what is a possible cause of error status 20087002 : 
'BIO routines:BIO_lookup:system lib'
This happens only once on Debian 9 standard OpenSSL package 
(1.1.0l-1~deb9u1)

Thank you in advance.

Kind regards,
Patrice.