We have been facing an issue since version 12.4 where the system at different times in the day will say that there was an error attempting to retrieve e-mail from an account we have specified. We have five different support queues with different accounts that mail can route through. These are all Gmail accounts and all the accounts at different times receive this message.
An example is:
An error last occurred at 9/26/18 9:03 am while attempting to retrieve e-mail from user@college.edu:
Unknown host: smtp.gmail.com
javax.mail.MessagingException: Connect failed;
nested exception is:
java.net.UnknownHostException: smtp.gmail.com
at com.sun.mail.pop3.POP3Store.protocolConnect(POP3Store.java:209)
at javax.mail.Service.connect(Service.java:295)
at com.macsdesign.whd.util.EmailUtils$1.executeUntilTimeout(EmailUtils.java:253)
at com.macsdesign.util.ThreadTimer$TimeableThread.run(ThreadTimer.java:138)
Caused by: java.net.UnknownHostException: smtp.gmail.com
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:184)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at java.net.Socket.connect(Socket.java:538)
at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:321)
at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:237)
at com.sun.mail.pop3.Protocol.<init>(Protocol.java:112)
at com.sun.mail.pop3.POP3Store.getPort(POP3Store.java:260)
...
Please check the e-mail account settings and the mail server for any problems. E-Mail will be checked again in 5 minutes, or when e-mail settings are updated to make a successful connection with your mailbox. Settings for this e-mail account are at Setup > E-Mail > Incoming Mail Accounts.
When we check the location that it specifies in Setup, all the accounts look good and there is no problem. This is a similar problem to what the Office365 users have seen.
Google has indicated that the issue is that WHD is attempting to send two requests at the same time to the account and it is temporarily locking the account. After 5 minutes the request will go through and begin working again. They (Google) have recommended changing the frequency that the request goes out to wait 2 seconds between sends. We have worked with WHD support on changing all kinds of settings on timings and in the end, there has not been a resolution. Having a configurable setting to set the requested retrieval may resolve this problem.
Thank you to KMSigma and adatole for your time and advise at VMworld, and the suggestion of posting this request.
