The post describes three issues of Microsoft System Center Virtual Machine Manager 2008 R2 issues that’re fixed in hotfix rollup package. Issue 1: If a virtual machine that was created from a template fails during customization phase, owner of vm cannot use self-service portal to connect to vm. Issue 2: Enable spoofing of MAC addresses option in vm properties is cleared when you configure network adapter to connect to a different virtual network. Issue 3: "Refresh host cluster" job can take more than 10 minutes to finish. To resolve, download a hotfix.
More info: KB976244