Issue: Unable to schedule meeting in Lync 2010.
Problem Statement: Clients are unable to schedule a Microsoft Lync 2010 meeting or conference call because either client cannot create meeting requests or others cannot receive them.
There is multiple cause of this issue. Many times client forget to unblock contacts due to that user facing lots of issues.
1. Make sure no participant is blocked from receiving meeting requests. If it recipients are blocked then change the privacy relationship from Block contacts to any other as per your choice.
2. If you can create meeting requests successfully but participants are not receiving them, have participants check their Junk E-mail folder for the invitation.
3. Make sure participants install the latest version of the Online Meeting Add-in for Lync 2010, if they are using a Microsoft Office 2010 suite, or the latest version of the Conferencing Add-in for Microsoft Office Outlook, if they are using Microsoft Office 2007 suites or Office 2003 suites.
4. Make sure your phone or device is optimized for Lync 2010. For a list of optimized devices, see “Phones and Devices Qualified for Microsoft Lync” at http://go.microsoft.com/fwlink/?LinkId=208938.
5. Have participants confirm with their support teams that their networks and accounts support Lync meetings.
6. If you are having issues with scheduling, see if others can schedule Lync meetings and conference calls. If no one can schedule or join a meeting, the issue is likely related to network connectivity. (For example, there might be an intermittent issue or temporary network outage.)
7. If you are scheduling a meeting with external contacts, make sure that your account is enabled for Enterprise Voice.