Offline files keep disappearing

Hi,

I've setup my latop so the Documents, Music and Pictures files point at the
same ones on my desktop and are availble offline. The idea is I can switch
between working on either when I'm at university or at home.

Generally it works fine expect I'm often find that the Documents, Music and
Pictures are unavailable the first time I login on my laptop (whited out in
the explorer) and I have to log off/on again to make them work - sometimes
multiple times.

It also sometimes happens when I connect to a different wireless network.

Any advice on anything I can do to either force Windox to find the offline
files or change my configuration so it works? At the moment it's great in
principle but just sometimes let down by the day-to-day hassel!!!

I'm on Windows Vista Ultimate.

Many thanks for your help,

Brendan