Can anyone help? I have a copy of sonar 5 producer, and have just bought a new computer and cannot get it to install I was going to upgrade to platinum but do I need to have sonar 5 on the computer first before I can upgrade.(sonar 5 is in my account and registered to me ) Thanks

There is no requirement to have a previous version of SONAR installed. The upgrade is the full retail version of SONAR at a special (i.e. upgrade) price.
 
In the future please post questions like this in the SONAR area above. This area is for discussion about the forum software, not Cakewalk products.