After installing 4.6c, I started the MMC and the SAP R/3 server by right-clicking. The color of the icon changed to yellow, then to green, then back to yellow.
I checked the syslog viewer, and it showed the errors:
R/3 Basis System Initialization DB-Connect Failed, Return code 000256
January 11, 2007 10:38 AM
April 6, 2011 11:43 PM