So I had WLM 2009, I just uninstalled that and then installed WLM 8.5. Now every single contact has been taken out of its category and they're all in 'Other Contacts'.
Took me ages to put all my 250+ contacts in groups
. Probably nothing I can do.
Checked on Web Messenger and they're all changed, so it's changed on the server not just my PC. Meh.
Consider this a warning for others thinking of doing the same.