Hi All, We use stunnel to send emails from our scanners to our hosted mail provider (that now only accept TLS connections). This has been working well for a number of years, but just recently the scanners (all Lexmark) have sporadically been giving errors of 'connection failed'. If I check the stunnel logs, the failed send has an extra line in of TLS socket closed (SSL_write) with 418 unsent byte(s) Below are 2 examples, 59 was sent successfully, 60 was not. 2018.01.16 14:37:24 LOG5[59]: Service [fasthosts-smtp] accepted connection from 10.226.174.95:11473 2018.01.16 14:37:24 LOG5[59]: s_connect: connected 213.171.216.50:465 2018.01.16 14:37:24 LOG5[59]: Service [fasthosts-smtp] connected remote server from 10.226.150.9:52577 2018.01.16 14:37:24 LOG5[59]: OCSP: Connecting the AIA responder "http://t2.symcb.com" 2018.01.16 14:37:24 LOG5[59]: s_connect: connected 23.55.155.27:80 2018.01.16 14:37:24 LOG5[59]: OCSP: Certificate accepted 2018.01.16 14:37:24 LOG5[59]: OCSP: Connecting the AIA responder "http://tj.symcd.com" 2018.01.16 14:37:25 LOG5[59]: s_connect: connected 23.55.155.27:80 2018.01.16 14:37:25 LOG5[59]: OCSP: Certificate accepted 2018.01.16 14:37:25 LOG5[59]: Certificate accepted at depth=0: C=GB, ST=Gloucestershire, L=Gloucester, O=Fasthosts Internet Limited, OU=NOC, CN=smtp.livemail.co.uk 2018.01.16 14:37:29 LOG5[59]: Connection closed: 167106 byte(s) sent to TLS, 376 byte(s) sent to socket 2018.01.16 14:38:19 LOG5[60]: Service [fasthosts-smtp] accepted connection from 10.226.174.95:11483 2018.01.16 14:38:19 LOG5[60]: s_connect: connected 213.171.216.50:465 2018.01.16 14:38:19 LOG5[60]: Service [fasthosts-smtp] connected remote server from 10.226.150.9:52620 2018.01.16 14:38:19 LOG5[60]: OCSP: Connecting the AIA responder "http://t2.symcb.com" 2018.01.16 14:38:19 LOG5[60]: s_connect: connected 23.55.155.27:80 2018.01.16 14:38:19 LOG5[60]: OCSP: Certificate accepted 2018.01.16 14:38:19 LOG5[60]: OCSP: Connecting the AIA responder "http://tj.symcd.com" 2018.01.16 14:38:19 LOG5[60]: s_connect: connected 23.55.155.27:80 2018.01.16 14:38:19 LOG5[60]: OCSP: Certificate accepted 2018.01.16 14:38:19 LOG5[60]: Certificate accepted at depth=0: C=GB, ST=Gloucestershire, L=Gloucester, O=Fasthosts Internet Limited, OU=NOC, CN=smtp.livemail.co.uk 2018.01.16 14:38:24 LOG3[60]: TLS socket closed (SSL_write) with 418 unsent byte(s) 2018.01.16 14:38:24 LOG5[60]: Connection reset: 964 byte(s) sent to TLS, 392 byte(s) sent to socket Has anyone come across this before? Our mail provider has send limits in place of 50 every 10 minutes, but I am confident we are not reaching those amounts. Any help appreciated. Regards, Stephen