What will be in ExManLog.YES doesn't matter. Extension Manager CS6 will create log files as long as this file exists, regardless of its content.
If the paid one didn't overwrite the free one, you can go to "C:\Users\<UserName>\AppData\Roaming\Adobe\Extension Manager CS6\EM Store\Dreamweaver CS6" folder and delete ajxcssmenu2.3.0.mxi, ajxcssmenu2.3.0.mxi_air and ajxcssmenu2.3.0.mxp then retry provided that you only installed it for yourself. If you installed it for all users, go to "C:\ProgramData\Adobe\Extension Manager CS6\EM Store\Dreamweaver CS6" folder instead.
Dear Carl, thanks for the advice that made me understand how to remove an extension without using the Extension Manager. However, the problem persists, i.e the Extension Manager freezes soon after it is launched, when the last 30 percent of the loading extension bar is still unaccomplished.
Following your instruction I have tried to remove both my versions of the troublesome DW extension (Ajatix Advanced CSS Drop Down Menu). Which in my case meant that I deleted the following files:
the files com.ajatix.AdvancedCSSMenuLight.mxi, com.ajatix.AdvancedCSSMenuLight.mxi_air and com.ajatix.AdvancedCSSMenuLight.zxp in C:\Users\<My UserName>\AppData\Roaming\Adobe\Extension Manager CS6\EM Store\Dreamweaver CS6
and the files ajxcssmenu2.3.0.mxi, ajxcssmenu2.3.0.mxi_air and ajxcssmenu2.3.0.mxp in C:\ProgramData\Adobe\Extension Manager CS6\EM Store\Dreamweaver CS6
In the hope of cleaning out everything from this extension I have also deleted the following files:
AJXCSSMenu.chm, AJXCSSMenu.dll in C:\Users\UpdatusUser\AppData\Roaming\Adobe\Dreamweaver CS6\en_US\Configuration\JSExtensions
and AJXCSSMenu.chm, AJXCSSMenu.dll, AJXCSSMenuLight.chm, AJXCSSMenuLight.dll in C:\Users\ipb-master\AppData\Roaming\Adobe\Dreamweaver CS6\en_US\Configuration\JSExtensions
Every time I thus get rid of the Ajitex files the Extension Manager seems happy and loads the only extension I currently have left (Adobe exchange). However when I reinstall the Ajitex extension, the Extension Manager behaves in the same bad manner, freezes after approximately 70 percent of the process of loading extensions. Same thing when I remove this extension and try to install another from Ajitex (Email Spam Blocker). It seems to install all right but afterward the Extension Manager freezes when launched.
Don't know what to do now.