To be honest, I'm not surprised you might have been having problems on a
Windows 7/8 PC if WL had not been installed simply to C:\Weatherlink, which
is always the recommended folder nowadays**. There are all sorts of
potential security clashes if it's buried in \Program Files somewhere. There
are possible workarounds, though not always reliable, but it's 100% simpler
just to use C:\Weatherlink.

** Yes, I know that WL used to default to installing in the \Program Files\
folder once upon a time, but that was several years ago and before the
security changes that really started with Vista and then matured more in
7/8. The only folder recommended for installation now is C:\Weatherlink.

John Dann
www.weatherstations.co.uk