Vista - Problems signing in WLM Version 2009, Build 14.0.8089.726

In the past I already had problems signing in WLM Version 2009, so I decided
to uninstall it and reinstall the previous version. However, since yesterday
it is not possible anymore to use this previous version. Microsoft forced me
to install the newest version of WLM (Build 14.0.8089.726), because of
security issues.

Again I am confronted with the same problem. Each time I want to sign in an
error message is shown. It says that Windows Live Communications Platform
encountered an error and needs to be closed.

Further details:

AppName: wlcomm.exe
ModVer: 5.1.2600.5755
AppVer: 14.0.8098.930
Offset: 0001b21a
ModName: ntdll.dll

Exception Information

et cetera

It seems many people have similar troubles. Still, I have not found any
useful solutions.

Please help me out.

Addition the previous message:

Exception Information

Code: 0xc0000005