We recently upgraded our Office from 2003 to 365 Small Business Premium.
We currently use Microsoft Exchange 2007 for mailbox storage, but use POP for sending/receiving emails. All of our PCs are running Windows 7 Pro.
There are two critical problems that all of our users are experiencing with Outlook 2013 calendar items:
1. When setting up an invite on a new calendar item, the mail server always defaults to the Exchange Server instead of the POP account. Users must remember each time to change the mail server to the POP, otherwise it get's lost on the exchange server. This
does not happen when sending emails, only calendar items.
2. After sending the calendar item via the POP account, it is not received by it's recipient. It's shown as "sent" but no one is receiving calendar items. (A serious problem!)
Please let me know if you need any additional information to help resolve this. (This is my first post, so please forgive me if I've excluded some obviously important information)
It seems that you are running into serious problems. Why don't you use Exchange as default and get rid of the POP. the only reason being that any Calendar invitation sent using POP would not be recognized by the external client.
Further you need to take up the issue with your POP service provider to find out if the items has left their server. Further it is not possible to track any information over internet for POP.
Exchange 2007 is very reliable for meeting requests and appointments. There might be chances that the people external to your organization have exchange servers which does not recognize the request send via POP.
At this point of time I would suggest you to check with your POP service provider and if required please open phone support case with Microsoft as we need to do extensive troubleshooting and collect various logs which is not possible via this FORUM.
You can always contact Microsoft Customer Central on 1-800-936-4900 to create phone support case. Alternatively you can visit
http://support.microsoft.com/oas to create case online
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