ELMAH with asp.net 4.0 on Test Server.

Using ELMAH for the first time.  And I have part of it working, stores an error to the db, and emails the error to me, but the actual "Hello World" default page won't load.  give me a message that says the following and to make a registry edit.   YIKES.   I'm a little nervous about making this registry value change.   Have you encountered this before? 
Parser Error Message: Could not load file or assembly 'Elmah' or one of its dependencies. The system cannot find the file specified.


WRN: Assembly binding logging is turned OFF. To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1. Note: There is some performance penalty associated with assembly bind failure logging. To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].
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