Had this problem on a Precision 3630 with DCU 3.1.3. Ran it over a weekend and came back to find it still stuck at 10%. Tried repairing, removing, and re-installing. Didn't help. Tried disabling the Dell service, renaming the folders in the ProgramData folder, didn't help. Uninstalled it, installed DCU 3.1.1 and that seems to have worked. So... bug in 3.1.3.
I've tried literally everything, every version since the initial 3.1 to the latest 3.1.1 and all give the same result "Operation is 10% completed..." Uninstalled, Installed rebooted and rebooted again, rename folders, repair, services you name it I tried. I called Dell Support and explained each step that I had taken and was hoping that there was a registry entry to delete/apply to fix the error or something buried in the installation location that could be modified to allow the DCU to work again but the Dell Support Technician said that I had to reimage my laptop!! Seriously what kind of solution is that, the application has always be buggy..but reimaging is just too much and just ridiculous.C'mon dell
A quick search of Dell Support yielded the answer. Here's what Dell support quotes as the problem.
"Dell Update and Alienware Update communicates with the Dell Client Management Service to perform the update tasks invoked by the user. When the user clicks "Check" on the Welcome screen, the application calls the service to perform a scan for updates. The service, in turn, will open C:\ProgramData\Dell\UpdateService\Clients\Update\Scheduler.dat to check for any scheduled tasks.
When Scheduler.dat is corrupted, the service gets an error and does not report back to the application which is expecting a response from the service. The application is left waiting and displays the last progress information that it received."
Follow the instructions and it corrects to problem.