The Symantec Endpoint Protection Manager web console is not accessible after installing Windows Security Update 956572 (MS09-012). After the trust certificate step, Internet Explorer remains on the localhost:9090 page.
There is no visible error message in Internet Explorer. Other browsers might display "Error 310 (net:: ERR_TOO_MANY_REDIRECTS)".
The issue is caused by changes that were made to the base address of Advapi.dll after installing Microsoft Windows 2003 Server Security Update MS09-012.