[sane-devel] Xerox PE220 scanner not detected

[Graham]

I have not been able to use my scanner with Linux for some years now (it 
works find with windows).  I am currently using Linux Mint 19.

All connections are good, printer is powered and operates normally 
(except scan).

sane-find-scanner
found USB scanner (vendor=0x0924 [Xerox], product=0x420f [Xerox 
WorkCentre PE220 Series]) at libusb:001:004

scanimage -L
No scanners were identified.

edited file
/etc/sane.d/xerox_mfp.conf

added
#Xerox MFP
usb 0x0924 0x420f

I suspect it may be a permissions issue but I am unable to resolve.

Any ideas please.

Cheers
Graham