Microsoft Exchange OLEDB was unable to register OnSyncSave event for Schema propagation on MDB startup HRESULT = 0x8000ffff.

Cause:
More than one schema-root object is listed in your public folders (the system public) folders, its trial and error to discover which one to get rid off, but non destructive.

Fix:
1. Open Exchange system manager
2. Expand Administrative Groups > First administrative group > Folders > Right click > Select "View System Folders"
3. Is there more than one schema-root? If so rename the oldest one to OLDSchema-rootOLD
4. Start > Run > Services.msc
5. Locate the "Microsoft Exchange Information Store" And right click > Restart
6. Start > Run > Eventvwr.msc make sure there are no 1194 or 111 errors if there are you renamed the wrong one.

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