I am having the same problem. Connection to Exchange server 2013 on port 587 to a receive connector with TLS enabled and basic authentication only after TLS. TLS connectivity works from other clients and I have tested successfully with openSSL to confirm that TLSv1 is working on that port. When I try a test from Visualcron, however, it fails with "Connection test failed. Error: Unhandled error: Connection failed (error code is 75777)"
I am using the following settings:
Port: 587
Code page: Windows-1252
Authentication: (user and password)
Cryptographic protocol: TLS
Security mode: Explicit
Proxy: none
My exchange logs show a connection attempt from the client, bu as soon as the exchange server responds, the client resets the connection:
2015-05-05T15:46:09.141Z,MX1\Client Frontend MX1,08D241B9527E25D4,0,<Exchange server>:587,<VisualCron>:65027,+,,
2015-05-05T15:46:09.141Z,MX1\Client Frontend MX1,08D241B9527E25D4,1,<Exchange server>:587,<VisualCron>:65027,*,None,Set Session Permissions
2015-05-05T15:46:09.141Z,MX1\Client Frontend MX1,08D241B9527E25D4,2,<Exchange server>:587,<VisualCron>:65027,>,"220 xxxx.com Microsoft ESMTP MAIL Service ready at Tue, 5 May 2015 08:46:08 -0700",
2015-05-05T15:46:12.068Z,MX1\Client Frontend MX1,08D241B9527E25D4,3,<Exchange server>:587,<VisualCron>:65027,-,,Remote(ConnectionReset)
If I switch to the SSL cipher, the connection succeeds using SSLv3, but I can find no way to successfully send using the TLS cipher.
As I mentioned, I have confirmed that TLSv1 is enabled and functional on this connector:
C:\Windows\System32>openssl s_client -connect XXXX.com:587 -starttls smtp
Loading 'screen' into random state - done
CONNECTED(00000194)
depth=2 C = US, XXXX
verify error:num=20:unable to get local issuer certificate
---
Certificate chain
XXXXXX
---
Server certificate
-----BEGIN CERTIFICATE-----
XXXX
-----END CERTIFICATE-----
subject=XXXX
issuer=XXXX
---
No client certificate CA names sent
Server Temp Key: ECDH, P-384, 384 bits
---
SSL handshake has read 5186 bytes and written 563 bytes
---
New, TLSv1/SSLv3, Cipher is ECDHE-RSA-AES256-SHA
Server public key is 4096 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
SSL-Session:
Protocol : TLSv1
Cipher : ECDHE-RSA-AES256-SHA
Session-ID: XXXX
Session-ID-ctx:
Master-Key: XXXX
Key-Arg : None
PSK identity: None
PSK identity hint: None
SRP username: None
Start Time: 1430844175
Timeout : 300 (sec)
Verify return code: 20 (unable to get local issuer certificate)
---
250 CHUNKING
EHLO test
250-XXXX.com Hello [XXX.XXX.XXX.XXX]
250-SIZE 10485760
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-AUTH LOGIN
250-8BITMIME
250-BINARYMIME
250 CHUNKING