Hi DarlinB,
We do not support Parallels Desktop 4 any more as it is an EOL (end of life) product for us. The support is provided for the latest version i.e., Parallels Desktop 10 and for the previous 2 versions (Parallels Desktop 8 & 9) only. We would suggest you to purchase a full product of Parallels Desktop and we will be glad to offer you support with it.