Error code: 4 CreateFile() Win32 Error: 32

Hi, I've seen alot of posts regarding error code 4, but this seems related to uploading files. I have a client who is using WinSCP to download files.

Cannot open remote file "/filepath/filename"
General failure (server should provide error description).
Error code: 4
Error message from server (en): The requested file can not be opened. Unexpected error. CreateFile(): Win32 Error: 32

Common reasons for the Error code 4 are:
- Renaming a file to a name of already existing file.
- Creating a directory that already exists.
- Moving a remote file to a different filesystem (HDD).
- Uploading a file to a full filesystem (HDD).
- Exceeding a user disk quota.

In the SSH server logs, I simply see OpenFile() failed. Error = 32
It says it can't open the file, but yet when I search on Win32 Error: 32 I see the definition is "The process cannot access the file because it is being used by another process". I checked the logs to see if maybe the file was being uploaded to the server the same time as they were trying to download the files. The file was uploaded to the server at 03:46 CT. The client was downloading at 07:33 CT so that isn't the case.
I checked the SSH logs and don't see more than one connection at the same time so it's not the case of two different users downloading the same file.
The SFTP server is Windows and the client computer is also Windows.
Any ideas?

This is not really a WinSCP question.
Anyway, is the problem intermittent or permanent? Can you delete/move/edit/whatever the file when logged in directly to the server (not via SFTP)? Did you try turning off server antivirus temporarily?

The client says it is intermittent. I see from the logs they are downloading multiple files and then get the error. The error happened twice for one file (they eventually were able to download) and is happening 20 times for the other. They are all zip files containing a various number of reports that were generated out of their financial system.
They are using WinSCP, but have asked them to try with another FTP client. I have a test SFTP account where I copied 400+ files from their folder over to my test folder (so yes, can move the folder) and downloaded multiple times without issue, including they one they have attempted to download 20 times. This was on the 24th. I was also able to open the zipped file without issue, so it's not corrupt. I was also able to delete all the files from my test folder.
I am also using WinSCP (5.21.8). From the logs they are using 6.1.1.
I will ask that they try without their antivirus and that they try with another FTP client.