SQL help-retrieve part of string

I want to retrieve only part of the string from the below input string.
These are 3 sample records,the name part is 'whalley-g' and 'whalley-l',so i want to get only the name part.

\\VBOXSVR\Desktop\maildir\whalley-g\inbox\498_   
\\VBOXSVR\Desktop\maildir\whalley-g\calendar\27_   
\\VBOXSVR\Desktop\maildir\whalley-l\all_documents\108_

Thank you

this has been done,thanks.