We have IIS/FTP 7.5, Windows 2008 R2 SP1, current patches. Site config: Actual FTP root unused. All Virtual Directories are on other disk volumes, one for each customer. They log in by appending the VD thus: ftp://ftp.redacted.com/VD
This is a standalone server with no AD membership. All FTP users are local Windows users.
Now one customer has a script that they can't modify and that can't traverse folders or append the VD. So we tried to do one instance of User Isolation. We only want this one user to be configured this way because we do not want to change the larger structure and disrupt all the other customers and their present login procedures for just this one customer.
We created a new disk volume like the others (this is a VM server) for the new customer as usual, and set the permissions. We created the root folder with the user-named folder underneath and set the VDat the user folder (NOTE: we have also named the root folder after the user, and also "LocalUser" with and without a VD set there, and a LocalUser folder UNDER the root with its own VD entry and without, and with the user ID folder under that, with and without its own VD). We already had Basic Authentication enabled for the whole FTP site and each VD. We set Authorization specifically for admins and the user in all cases for the abovementioned VDs.
Now for the User Isolation settings: because we only want this one user affected, we can't choose User Name Physical Dir with disable global. We have tried both User Name Physical with globals enabled and Do Not Isolate/Start in User Name directory. We can get both to work (the former required that we move the target folder to the root where we do not want it). The user ID in question can log on, and is directed to the folder we want. But something weird happens: when we test it and upload a file successfully (or copy a file into the folder manually on the server), the file sits for a bit and then disappears.
We can't trace what is deleting the file or why. Help!