Problem with sending output to a mapped drive

We run a 'backup' job every Saturday.
The backup job normally keeps its output locally on the C: drive,, but now I have been asked to configure the backup job to store backups to a mapped drive.

The folder on a Windows 2016 server is shared.
The windows user logged on to the computer running CatTools is a user who has rights to the shared drive
The job is configured to forward each config file to the shared drive,, (Lets call it the K: Drive) ,,, but the files are never copied.

I then ran a simple job on one device for "Show NTP" & save the "Report:" to the same K drive.

This job runs. The report is not sent to the K drive,,
I receive an "Errors" email about the job.

It says "

Unable to write to file: K:\Device.CLI.Send commands.htm. Error: Path not found

I have tried to stop & start the CatTools service from the Services.msc,, but even then the file will not save to the mapped drive.

Manually,, I can copy the file from the computer where CatTools is running to the same drive,.
The path is there.
What can I do to ensure that CatTools can copy files to the mapped drive ?