You may see event ID messages that are similar to the following event ID messages in the System Log:
1/15/2002 6:42:48 PM DCOM
EventID: 10002
Access denied attempting to launch a DCOM Server. The server is:
{9DA0E106-86CE-11D1-8699-00C04FB98036}
The user is SYSTEM/NT AUTHORITY, SID=S-1-5-18.
WORKAROUND
To work around this issue, set all three of the following SharePoint Portal Server services to Manual before you install the MDAC 2.7 update.
MSExchangeIS
MSSearch
MSDMServ
After you have finished installing the MDAC 2.7 update, reset the services that are listed in this section to Automatic, and then restart SharePoint Portal Server.