We're using the IMAP components to connect our software to customer mailboxes and while it's been working fine for all, I've had a report in this morning from one particular customer that they get nothing but error messages back. I think it's something on their network (e.g. Firewall) but they've been running some tool from Microsoft that claims that everything is fine, Outlook can connect without any problems etc. They also claim to have checked their firewall to make sure that port 993 is open.
I've tried to connect using the customer's details and do indeed get an error out (verbose log below) but connecting to our own mailboxes or webmail (e.g. Gmail) is working absolutely fine. Having stepped through our code it looks to be failing when connecting and never even reaches the login stage.
Unable to connect to server. The following error was returned: ChilkatLog: Connect_Imap(47ms): DllDate: Feb 13 2015 ChilkatVersion: 18.104.22.168 UnlockPrefix: **** Username: **** Architecture: Little Endian; 64-bit Language: .NET 4.0 / x64 VerboseLogging: 1 connectToImapServer(47ms): hostname: **** port: 993 socket2Connect(47ms): connect2(47ms): hostname: **** port: 993 ssl: 1 connectImplicitSsl(47ms): connectSocket(31ms): domainOrIpAddress: **** port: 993 connectTimeoutMs: 30000 connect_ipv6_or_ipv4(31ms): Multi-threaded domain to IP address resolution connecting to IPV4 address... ipAddress: **** createSocket: Setting SO_SNDBUF size sendBufSize: 262144 Setting SO_RCVBUF size recvBufSize: 4194304 --createSocket connect(31ms): Waiting for the connect to complete... myIP: **** myPort: 64051 socket connect successful. --connect --connect_ipv6_or_ipv4 --connectSocket clientHandshake(16ms): clientHandshake2(16ms): readHandshakeMessages(16ms): numBytesRequested: 5 Connection closed by peer. passiveClose: Passive socket closing complete. --passiveClose Failed to read beginning of SSL/TLS record. --readHandshakeMessages --clientHandshake2 --clientHandshake Client handshake failed. (3) --connectImplicitSsl ConnectFailReason: 0 --connect2 --socket2Connect failReason: 0 --connectToImapServer connect failed. --Connect_Imap --ChilkatLog
Never mind. I updated to the latest version of the IMAP component (v22.214.171.124) and it seemed to do the trick.
It seems that the customer had switched to Exchange 2013 and something in the configuration didn't sit well with v126.96.36.199