Can't login to Admin

I have been "playing" with the css this morning.  Changing text color is about all that I did.  I did upload a new logo image.  I am using Visual Web Developer Express 2010.  I am now no longer able to access "admin".  I am able to log in as "admin" but I get a "internal error generic error.  Any ideas on what I have done?

Earlier today the entire web site was down.  a web config error.  I was able to revert to the previous copy of web.config and restored the web site...could this be the culprit for "admin" not being available?

Thanks

Open up web.config and change:

<customErrors mode="RemoteOnly" defaultRedirect="ErrorPage.htm">

to:

<customErrors mode="Off" defaultRedirect="ErrorPage.htm">

Now try and run your site again and you will get a more informative error message. Please post this to the forum.


Larry

Not sure which part is necessary so this is the entire error...

Server Error in '/' Application.
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Parser Error
Description: An error occurred during the parsing of a resource required to service this request. Please review the following specific parse error details and modify your source file appropriately.

Parser Error Message: Could not load file or assembly 'AjaxControlToolkit' or one of its dependencies. The module was expected to contain an assembly manifest.

Source Error:


[No relevant source lines]


Source File: none    Line: 0

Assembly Load Trace: The following information can be helpful to determine why the assembly 'AjaxControlToolkit' could not be loaded.


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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