We were able to identify this issue and create a patch. You will need to be on LDMS 9 SP2. To get the patch, please call support and open a case.
Thanks for the post, this did help someone, it was, the key, to us finding out the cause of slow boot ups,
How did you identify this key?
In our case it is UNS.exe (AMT user notification service) that is making the HKU\.Default\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Digest\Host key huge,
Using procmon, UNS.exe writes a new subkey every 5 minutes
Did you find a more permanent fix?
I am considering disabling the UNS service, it appears its main function is to allow AMT to write to the event viewer
The patch didn't work for me. The only way I had of finding the key was to run procmon and see what reg key was being written. I had some machines that took 3 days to bootup. Then they were so slow that the user couldn't do anything. I am the only one in our IT Department that used AMT, so I just disabled it. Kinda sorry I did that, and did not persue a permanent fix that allowed AMT to remain active. Sure would like to see if someone can resolve this, and then maybe I will reenable AMT.