Where do you found this info?WU/MU lists 2728973 in the "important" list. It is also requested by automatic updates, it is definitely NOT optional. It also installs silently when just running it w/o params. The problem is that the cmd-params doesn't fit for HFSVCPACK_SW1 and HFSVCPACK_SW2. So, for HFSLIP you have to put it to HFSVCPACK!I believe you're wrong, mimo, placing rvkroots in HF works perfectly. Please test it (I did). After installation, it's not requested by neither auto updates nor by visiting windowsupdate.com and neither as important, nor as optional. Please test it!!! CU, Mimo