We have successfully built sites with versions before 3.0 using this plugin, but are have not been able to install on 3 sites.
Plugin shows in FTP but is not acknowledged by WordPress Editing System. We have tried to install 3 different ways with the same problem using Themes: Orange Wood 1.0, Belona and Vivid 1.0.
On all three, when we try to install we get the following message:
Destination folder already exists. /public_html/wp-content/plugins/contact-form-7/
Plugin install failed.
We would like to continue using this plugin because most of our clients require more than one contact form.