I have attempted to uninstall and reinstall eMail Client to resolve the subject issue, to no avail. The program will not retrieve or send mail. Here is a copy of the log after uninstall and reinstalling:
6:39:18 AM Online state: changed to online due to NetworkAvailability
6:39:18 AM Tx.rr (mark.williams9) [POP3] Connecting: To Tx.rr (mark.williams9)
6:39:18 AM Tx.rr (mark.williams9) [POP3] Connected: To Tx.rr (mark.williams9)
6:39:19 AM System.ArgumentException: An item with the same key has already been added.
6:39:19 AM at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
6:39:19 AM at System.Collections.Generic.Dictionary
2.Insert(TKey key, TValue value, Boolean add) 6:39:19 AM at MailClient.Protocols.Pop3.Pop3Account.CheckUids(IEnumerable1 uidsList)
6:39:19 AM at MailClient.Protocols.Pop3.Pop3ReceiveCommand.Execute(WorkerStatus status)
6:39:19 AM at MailClient.Commands.Command.Process(WorkerStatus status)
Searching this forum I see that it is an ongoing problem with no apparent resolution. At the moment I will need to uninstall the program and use my old e-mail app.