Package Load Failure

I get the error:

Package Load Failure
Package 'Microsoft.SqlServer.Tools.PublishWizard.VSCommands.MenuCommandsPackage, MenuAndCommands, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bg3856ad364e35' has failed to load properly ( GUID = {A38CF415-6AD2-45F6-8132-9CC33EBE0629}).

I get this error after I have opened VS and then open the Server Explorer Window.

I have been using VS2005 Professional since December of 2005 and have never encountered this before. I have never had a beta version of anything on this PC. I have been searching the Net but haven't found a solution. At this point, I haven't tried reloading VS because even if it does fix it, what is the guarantee that I will not encounter it again. I would rather find and fix the cause.

Does anyone have any ideas?

Additional: I have now uninstalled and reinstalled VS2005 and SQL Server 2005 including service packs and am still getting the error.



Additional:
When I ran devenv.exe, the section of the resulting log referencing the GUID indicated an invalid Package Load Key:

<entry>
<record>56</record>
<time>2007/11/15 15:23:53.647</time>
<type>Information</type>
<source>Microsoft Visual Studio</source>
<description>Entering function CVsPackageInfo::HrInstantiatePackage</description>
<guid>{A38CF415-6AD2-45F6-8132-9CC33EBE0629}</guid>
</entry>
<entry>
<record>57</record>
<time>2007/11/15 15:23:53.647</time>
<type>Warning</type>
<source>Microsoft Visual Studio Appid Stub</source>
<description>CheckPackageSignature failed; invalid Package Load Key</description>
<guid>{A38CF415-6AD2-45F6-8132-9CC33EBE0629}</guid>
</entry>
<entry>
<record>58</record>
<time>2007/11/15 15:23:53.663</time>
<type>Warning</type>
<source>Microsoft Visual Studio Appid Stub</source>
<description>CheckPackageSignature failed; invalid Package Load Key</description>
<guid>{A38CF415-6AD2-45F6-8132-9CC33EBE0629}</guid>
</entry>
<entry>
<record>59</record>
<time>2007/11/15 15:23:53.663</time>
<type>Warning</type>
<source>Microsoft Visual Studio Appid Stub</source>
<description>CheckPackageSignature failed; invalid Package Load Key</description>
<guid>{A38CF415-6AD2-45F6-8132-9CC33EBE0629}</guid>
</entry>
<entry>
<record>60</record>
<time>2007/11/15 15:23:53.663</time>
<type>Warning</type>
<source>Microsoft Visual Studio</source>
<description>Appid denied the loading of package</description>
<guid>{A38CF415-6AD2-45F6-8132-9CC33EBE0629}</guid>
</entry>