Cant delete old license keys from server?

Hi All

Ive got an issue where I've got two old licenses keys stuck in my vcenter server Licensing section, ive tried removing them by right clicking and choosing remove, and also using the manage my licenses wizard but after it does it I then refresh and they re-appear.  So i followed this kb :-

http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1015268

Which shows how to delete them using ADSIedit which i have completed but again when doing a refresh the keys reappear, so i found this HP KB :-

http://h10025.www1.hp.com/ewfrf/wc/document?cc=au&lc=en&dlc=en&docname=c02684357

Which interestingly says to stop the vcenter services before doing the ADSIedit steps (when the VMware one doesnt), what is everyones thoughts/experience on this?  stop the services?

We are running in linked mode, if that makes a difference.

thanks

Stewart