We have a single Server 2008 R2 with Exchange 2010 SP3 CU12 server installed, that suddenly has started to do the following.
Some users(3-5 out of 70) cannot send mail from their iPhone, iPad or Outlook 2011 and Outlook 2016 for Mac or webmail. Mails send ends up in drafts and then they can login to the webmail and send and then it sends without problems, but even sending from webmail results in drafts first, reopen mail and send, and then it sends. We can make it function again by restarting the store service, and then it works for about half a day. Our log files does not show anything... Windows Outlook works perfectly all the time, even for the users haveing this problem!
Please help, as we do not know where to look anymore :)
Thank you in advance
Active DirectoryExchangeEmail ProtocolsEmail Clients
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