Service Pack installation will fail, if you have not logged in as a Domain Administrator that has been specified in the Scope of Management. Login to the computer with the Domain Administrator credential and then install the Service Pack.
One possible reason could be that the Desktop Central agents in the client computers are not upgraded to the latest. Whenever there is a change in the version, it gets automatically upgraded during the next user logon in the client machines. It should be noted that the user should have the same or higher privileges as that of the user on whose account that the Desktop Central agent was initially installed. Check the Agent version from Admin --> Scope of Management link.
Download the latest Service Pack or the Hotfix from our website and follow the instructions below to install them: