Google Base product feed problems

Hi,

I have enabled Google base on my site, and have the URL which is:

http://simplysowseeds.co.uk/index.php?r ... oogle_base

When I try and load this into Google Base I get:

Data feed file name (Example: data_feed.txt)

Note: Filenames with special characters are not supported
These characters are not allowed: /,:,=,?

Can you help?

Thanks

Peter Jones
www.simplysowseeds.co.uk

The Feed URL is entered in the Scheduler - You can call the feed name anything you like such as google.xml