cannot set directory locks for the following folders: Error code 0xffffffff

[Pilgrim_Li]

I got this warning when I synced on both windows pc and mac. How to fix it? Thank you!

Cannot set directory locks for the following folders:

Cannot write file "I:\Desktop\sync.ffs_lock".
Error code 0xffffffff [CreateFile]

[Pilgrim_Li]

I got the same warning even after I created a new sync rule for the folders. Does it mean my disk drive goes wrong?

[Zenju]

Looks like a bug in the network drivers. 0xffffffff is returned by GetLastError(), which isn't a valid error code and should never happen.