Got to page 10 of Google without even finding a mention of this, so its over to Arrse IT support: I'm about to start up a fresh OEM installation of Win7 Home Premium on a laptop. I want to know if the default username - which of course has to chosen as part of the normal Windows set-up - can be a number, or whether it has to be composed of letters instead? I'm trying to solve an issue of using English language application on a Russian Win7 installation; briefly English apps can't recognise a username written in Cyrillic, and Russian apps can't recognise a username written in latin script. The only commonality between the different language character maps is the number keys. hence my sneaky plan to use numbers instead of charcaters.