Script to save file to disk1

Hi All
I am new to scripting to please can someone help with the syntax for this script, It saves file perfectly to built in disk but not to external disk1 (which is visible and working okay)
This works:
:global backupfile ([/system identity get name] . “-” . [/system clock get time])
/tool user-manager database save name=$backupfile

This doesn’t work
:global backupfile ([/system identity get name] . “-” . [/system clock get time])
/tool user-manager database save name=/disk1/$backupfile

I have highlighted the only change between the two scripts in red and have tried it with and without a forward slash in front of disk1. Thanks in advance for your help!

Graham

=“disk1/$backupfile”

That worked! Thanks very much indeed!