Hi Alan, Thanks heaps, that worked. I’d tried double and triple, but not four, which makes sense in hindsight. I forgot to mention that I’m using v 2.2.6 Thanks Jason Rankin Senior Network Administrator | Information Technology Services Federation University Australia PO Box 663 Ballarat VIC 3353 Telephone +61 (03) 5327 9782 | Mobile 0417 595 045 j.rankin@federation.edu.au CRICOS Provider Number 00103D [http://federation.edu.au/__data/assets/image/0005/148361/eMail-Signature_150...] From: Alan Buxey [mailto:A.L.M.Buxey@lboro.ac.uk] Sent: Friday, 10 April 2015 11:04 PM To: FreeRadius users mailing list; Jason Rankin Subject: RE: backslash and expansion variable quirk in line log format string Sounds like you need \\\\ version 2.2.x needs backslash overload alan