I regularly read the Southern Arizona Revit User Group's blog. A recent post poked me in the eye and I thought I'd respond to it here. Here's the bit that poked me:
1. Make sure no one EVER edits a Central file directly, once local files have been created. If you do, you will need to recreate all the local files from the new Central file.
It's good advice, don't work in a central file.
The second sentence is what concerns me, it isn't accurate. If someone does work in the central file no harm is done by doing so. The worst thing that will happen is Revit will force that person to save the central file as a local file before allowing for synchronization to occur. If other people are actively working in their local files and someone opens the central directly they are very likely to get this message (after doing some work for awhile) when they attempt to save.
This dialog isn't guaranteed to appear no matter what. It only shows up when there is some conflict between the central file that is being edited and changes made in a local file. The more users there are the more likely it will show up.
The dialog title (Local File not Synchronized) is a little confusing because it appears when editing the central file and trying to save. It's the central file that couldn't save. The solution is to use Save As to create a new file (local file as a result) and then use Synchronize with Central (SwC) again.
Assuming it is necessary to work in the central file, the only way to completely avoid running into it is to only work on a central file when there are no other active local files in play.
Why would it be necessary to work in a central file? Read an earlier post.