<p>Thanks. Yes, I understood you, and checked there were no connections at all and no .lck file when the problem client tried to log in. Although, for info, I have tested with another remote client and in that case it will connect even if there is a .lck file as result of a local client being connected.</p><p>I suspect it is to do with SSL and will try setting that up again from scratch. </p>

<p>Two clients on old Nokia smartphones have recently developed a problem connecting to my Mercury server. It only affects the Nokia clients, not PCs or Android, and is intermittent - most connection attempts fail, but occasionally one succeeds.</p><p>The clients log of the conversation is (verbatim except [myservername] and [myserverIP])</p><blockquote><p>Connect Connection already active, using it Socket opened Connecting to host [myservername] 143 Connect to IP [myserverIP] Destroying socket Socket cancel:OK Socket close Ok *finished</p></blockquote><p> The Mercury sessionlog is (verbatim except [myservername] [username] and [passwordhash]</p><blockquote><p>20:23:06.646: --- 29 Nov 2017, 20:23:06.646 --- 20:23:06.646: Accepted connection from '82.132.226.79', timeout 120 seconds. 20:23:06.646: Connection from 82.132.226.79, Wed, 29 Nov 2017 20:23<cr><lf> 20:23:06.661: << * OK [myservername] IMAP4rev1 Mercury/32 v4.80.145 server ready.<cr><lf> 20:23:07.537: >> 1 CAPABILITY<cr><lf> 20:23:07.537: << * CAPABILITY IMAP4rev1 STARTTLS AUTH=PLAIN X-MERCURY-1<cr><lf> 20:23:07.552: << 1 OK CAPABILITY complete.<cr><lf>20:23:07.865: >> 2 STARTTLS<cr><lf> 20:23:07.865: << 2 OK Begin SSL/TLS negotiation now.<cr><lf> 20:23:09.521: [*] SSL/TLS session established 20:23:09.521: [*] AES256-SHA, SSLv3, Kx=RSA, Au=RSA, Enc=AES(256), Mac=SHA1<lf> 20:23:09.521: [*] No peer certificate presented. 20:23:09.646: >> 3 CAPABILITY<cr><lf> 20:23:09.646: << * CAPABILITY IMAP4rev1 AUTH=PLAIN X-MERCURY-1<cr><lf> 20:23:09.662: << 3 OK CAPABILITY complete.<cr><lf> 20:23:09.818: >> 4 LOGIN [username] [passwordhash]<cr><lf> 20:23:09.880: << 4 OK LOGIN completed.<cr><lf> 20:23:10.318: >> 5 SELECT INBOX<cr><lf> 20:23:10.334: << * 1 EXISTS<cr><lf> 20:23:10.334: << * 0 RECENT<cr><lf> 20:23:10.334: << * FLAGS (\Deleted \Draft \Seen \Answered)<cr><lf> 20:23:10.334: << * OK [UIDVALIDITY 1464263818] UID Validity<cr><lf> 20:23:10.334: << * OK [UIDNEXT 1194] Predicted next UID<cr><lf> 20:23:10.349: << * OK [PERMANENTFLAGS (\Deleted \Draft \Seen \Answered)] Settable message flags<cr><lf> 20:23:10.349: << 5 OK [READ-WRITE] SELECT completed.<cr><lf> 20:23:10.490: >> 6 FETCH 1:* (UID flags)<cr><lf> 20:23:10.490: << * 1 FETCH (UID 1188 FLAGS (\Seen \Answered) 20:23:10.490: << )<cr><lf> 20:23:10.490: << 6 OK FETCH complete.<cr><lf> 20:23:12.599: 26: SSL_read returned zero (socket was closed) 20:23:12.599: >> 20:23:12.631: [!] Warning: SSL connection improperly closed by remote host. 20:23:12.631: --- Connection closed normally at 29 Nov 2017, 20:23:12.631. --- 20:23:12.631: </p></blockquote><p> I am not aware of anything I've changed in either server or client configs since the time it all worked, but it may be a change in some external resource. Mercury is running on Windows 10.</p><p>Thanks for any advice/assistance. </p><p> </p><p> </p>

Are you certain the account is not being accessed locally when the IMAP connection is created?

Thanks for the suggestion. I have now checked, and the problem occurs whether or not other clients are accessing the account

<p>[quote user="Chris Bolton"]Thanks for the suggestion. I have now checked, and the problem occurs whether or not other clients are accessing the account [/quote]</p><p>I meant local connections i.e. from mail clients that access Mercury/32 from within the same network. Multiple IMAP connections can be made, but IMAP connections will fail if a local client is accessing the client because a .lck file is created which tells Mercury/32 the account is effectively 'locked'. Check the account folder and make sure no .lck file exists when this problem occurs. </p>