cannot install webroot

Hi freaves69
 
Welcome to the Community Forums.
 
Can you advise as to why you uninstalled your 'old' version of WSA (I am assuming that your 'old' version was post 2011) to install the 'new' version?  If you are running WSA post 2011 you should not need to uninstall...if yo purchase a new key then it is just the case of entering & activating that in the existing version.  If the new key was for a different 'version' to your currently installed one, i.e., going from Antiviruse to Complete then enteringt he new key unlocks the new features purchased.
 
I am also assuming that you have tried to uninstall WSA using the Uninstall Program applet from the Control Panel?  Well, if you are experiencing difficulties then please see this KB Article that should provide you with additional options to try.
 
Hopefully that will help, and if not then just post back here and we will look to try something else.
 
Regards, Baldrick