I've upgrated my Parallels 10 to 11 a few days ago. My Windows 7, 8.1 and 10 VMs working fine and fast. Yesterday I created a new VM with OS X 10.10.5 Yosemite. Works also fine. Because I have a Apple developer account, I have also access to OS X 10.11 El Capitan Beta. So I opened my OS X 10.10 VM, opened the Apple store (because I had already downloaded OS X 10.11 Beta 1 a few weeks ago) and started the download of the Beta 1 to install it over the OS X 10.10 VM. The installation starts as normaly. But after a few minutes I got a windows that says that the installation is not possible. What can I do? Is it right that I have to download first the Beta 1 to update it to Beta 7? Or is there a way to directly download the Beta 7? Thanks for help!