Connection Conflict Issue with POP3 setup

[Penoto365]

Hello all,

I am a new user, with the Maildroid free android version 3.7.4 just now installed on my 2 devices, one a Samsung Galaxy S4 running Android 4.4.3, the other an ASUS Transformer Prime (TF201) running 4.1.1. I had an issue setting it up for my pop3 account on the tablet after successfully sending and receiving messages on the phone. The setup gave an error message as follows:
"Error;
Password or settings are incorrect;
Protocol: pop3;
Error: [IN-USE] Unable to lock maildrop: Mailbox is locked by pop server."

I troubleshot it for a while and found that even with the Connection Management settings configured to "Close Connection when I exit the mailbox" and "Never check mail", the app keeps the connection locked so that my other device's email app cannot connect to download new messages. This issue exists on each device when accessing the server from the other device, and it also occurs on K-9 running on the same device so that if Maildroid is in background, K-9 will not download new mail until after I "Force-Stop" Maildroid in the Apps menu. It returns after I restart Maildroid and manually attempt to retrieve new mail on it.

The Authentication Error message for this behavior is shown below

The K-9 mail app is installed as well on both devices although it has well documented issues running on the Transformer. When I wish to, I can download new mail  both devices simultaneously using K-9, and there is no similar connection issue.

This seems to me to be a bug, but as a noobie I may have missed some configuration setting to make this work properly. I emailed the Dev hoping for some help earlier, and now I hope another user can steer me to the answer.

- TITLE -
Authentication error:

- PROBLEM -
[IN-USE] Unable to lock maildrop: Mailbox is locked by POP server
- SERVER -
Protocol: pop3
Host: capital.net
- TECHNICAL DETAILS -
Version: 3.74
javax.mail.AuthenticationFailedException;
  nested exception is:
 java.io.EOFException: [IN-USE] Unable to lock maildrop: Mailbox is locked by POP server
 at com.sun.mail.pop3.POP3Store.protocolConnect(POP3Store.java:209)
 at javax.mail.Service.connect(Service.java:328)
 at javax.mail.Service.connect(Service.java:194)
 at javax.mail.Service.connect(Service.java:219)
 at com.maildroid.ag.c.a(ConnectionUtils.java:31)
 at com.maildroid.ag.h.a(IncomingConnector.java:23)
 at com.maildroid.ag.d.a(ConnectorBase.java:394)
 at com.maildroid.ag.d.d(ConnectorBase.java:297)
 at com.maildroid.ag.d.c(ConnectorBase.java:140)
 at com.maildroid.ag.d.a(ConnectorBase.java:87)
 at com.maildroid.ag.l.a(MailUtils.java:54)
 at com.maildroid.second.aq.e(Pop3Session2.java:87)
 at com.maildroid.second.a.b(BaseSession2.java:93)
 at com.maildroid.service.ag.e(SessionController.java:234)
 at com.maildroid.service.ag.a(SessionController.java:167)
 at com.maildroid.service.ag.c(SessionController.java:142)
 at com.maildroid.service.ag.a(SessionController.java:97)
 at com.maildroid.service.ai.e(SessionControllerWithState.java:217)
 at com.maildroid.service.ai.d(SessionControllerWithState.java:190)
 at com.maildroid.service.ai.a(SessionControllerWithState.java:42)
 at com.maildroid.service.ad.a(RemoteMailService.java:140)
 at com.maildroid.m.d.a(MailService.java:43)
 at com.maildroid.bc.e.a(TasksExecutor.java:44)
 at com.maildroid.bc.g.run(TasksExecutorThread.java:18)
 at com.flipdog.commons.t.b.run(ThreadUtils.java:46)
 at java.lang.Thread.run(Thread.java:841)
Caused by: java.io.EOFException: [IN-USE] Unable to lock maildrop: Mailbox is locked by POP server
 at com.sun.mail.pop3.POP3Store.getPort(POP3Store.java:317)
 at com.sun.mail.pop3.POP3Store.protocolConnect(POP3Store.java:207)
 ... 25 more
- END OF REPORT -

Thanks in advance,
Tom