Here is the response I got from Magellan
Thank you for contacting Magellan. This email is in response to your query
about the MapSend Topo Canada.
Our Sincere apologies for the delay in responding your email.
We understand your mail that you get an error message while using Windows
vista.
In this case I would like to say you that All Magellan units are only
compatible with Windows 2000 and Windows XP.Currently we dont have any
drivers for Windows Vista.Once there is an update it will be posted in
our website.
I am confident that the above information would help you in resolving the
issue. If you have further queries, please get back to us.
You can also contact our Technical Support at 1-800-707-9971 for further
assistance.
Not too helpful.