I am in the process of taking over the administration of our SharePoint 2010 infrastructure. Following a support call from one user, we noticed that the names showing up on the sites are looking like DOMAIN\USERNAME.
I tried to use the tip provided by Gary Lapointe as described in his blog post: http://blog.falchionconsulting.com/index.php/2011/12/updating-sharepoint-2010-user-information/
Basically, it forces the profile to get loaded with AD information by issuing the below command:
Set-SPUser -Identity $user -SyncFromAD
This did fix the names on the page for a day. The next day, the names where back to DOMAIN\USERNAME.
Furthermore, while clicking on the name of "some" users, the redirection to their mySite fails with a 502 Time Out HTTP error. Other people profiles (I'm assuming people who did not generate a mySite before the migration) are accessible normally because the user is not redirected to mySite.
I reviewed the configuration of the server and noticed the following: the User Profile Synchronization Service is not started (and not configured) and no synchronization connection is defined). Therefore my question id threefold:
Can SharePoint work normally without having the User Profile Synchronization Service running?
Would configuring the service and the connection fix the display name / access to mySite issue?
Is there any downside of configuring the service after having content on the sites?