About once or twice a week at random at the beginning of the work day, I have to randomly restart our office Microsoft Exchange 2010 server due to Microsoft Outlook 2010 not receiving User Name and Password Credentials on all computers at my office. When this situation happens, some users are able to send/receive their Outlook e-mail just fine, while other users are unable to send/receive Outlook e-mail via Exchange. After I have restarted the exchange server and other users have either restarted their computers and/or Outlook, all users are able to send/receive e-mails just fine. I am not sure if this problem relates to recently download Microsoft Updates that required computer/server restarts that downloaded automatically overnight and users are not able to send/receive e-mails due to Outlook needing correct user name and password credentials. Please help me with any solutions that you might provide. Thanks.
Software/Hardware used: Microsoft Exchange 2010, Microsoft Outlook 2010, Windows Server 2008 R2, Windows 7, Windows XP