From our testing it appears the latest “click-to-run” versions of Office 2010 available from this page do not work well with OggSync 4.28.3. If you wish to use OggSync, we recommend uninstalling the click to run trial software, and instead use this version (Microsoft Office Professional Plus 2010). You can do this by using the following procedure:
1) Start ~ Control Panel ~ Uninstall A Program
2) Uninstall OggSync
3) Uninstall click to run Office 2010 and Click to run Office Installer
4) Go to this page and sign up for the Professional Plus Office 2010 Trial
5) Install this version (ProfessionalPlus.exe)
6) Reinstall OggSync
7) Reboot
We have also reproduced the new error “The server is not available. Contact your administrator if this condition persists.” A temporary workaround for this is to open the task manager, stop the OggSync and Outlook processes, start Outlook first, then start OggSync. We are looking into a fix for this issue.