I've gone through multiple posts and articles showing how to increase your RAM through Configure->Hardware when the VM is not running but I'm still unable to change the current amount allocated. I recently downloaded Parallels desktop 13 for Mac and have a new iMac purchased in the last year with 16 GB of RAM but I'm unable to allocate more than 2 GB. I get the same error message others have mentioned: "to be able to change the settings, resume the virtual machine and then shut it down." It doesn't matter whether the VM is running or not, still can't change the memory or hard disk settings. Any suggestions or advice is much appreciated!