If you have either a Mounted Volume or Junction Point that maps to the root of a volume you may find that this folder intermittently disappears when accessed through a shared folder.
The problem is caused by the SMBv2 Client Redirector Cache and has been acknowledged by Microsoft as a known problem in the following operating systems:
The problem can easily be observed by performing the following actions:
Note, all actions assume you are using one of the above operating systems in all cases
The following workarounds can be used to remove the problem:
Microsoft have released a knowledge base article to address this specific problem: