I have DNN 4.5.3 installed, and I keep getting repeated errors in the Event Log. Here there both are. Any Clues?

AssemblyVersion: -1
PortalID: -1
PortalName:
UserID: -1
UserName:
ActiveTabID: -1
ActiveTabName:
RawURL:
AbsoluteURL:
AbsoluteURLReferrer:
UserAgent:
DefaultDataProvider:
ExceptionGUID:
InnerException: Value cannot be null. Parameter name: type
FileName:
FileLineNumber: -1
FileColumnNumber: -1
Method:
StackTrace:
Message: System.ArgumentNullException: Value cannot be null. Parameter name: type at System.Activator.CreateInstance(Type type, Boolean nonPublic) at DotNetNuke.Framework.Reflection.CreateObject(String TypeName, String CacheKey) at DotNetNuke.Services.Search.ModuleIndexer.GetModuleList(Int32 PortalID)
Source:
Server Name: WINHOSTECN108

And the second error is:

AssemblyVersion: -1
PortalID: -1
PortalName:
UserID: -1
UserName:
ActiveTabID: -1
ActiveTabName:
RawURL:
AbsoluteURL:
AbsoluteURLReferrer:
UserAgent:
DefaultDataProvider:
ExceptionGUID:
InnerException: Could not load type ''.
FileName:
FileLineNumber: -1
FileColumnNumber: -1
Method:
StackTrace:
Message: System.Web.HttpException: Could not load type ''. ---> System.ArgumentException: String cannot have zero length. at System.Reflection.Assembly.GetType(String name, Boolean throwOnError, Boolean ignoreCase) at System.Web.Compilation.BuildManager.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase) --- End of inner exception stack trace --- at System.Web.Compilation.BuildManager.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase) at DotNetNuke.Framework.Reflection.CreateType(String TypeName, String CacheKey, Boolean UseCache, Boolean IgnoreErrors)
Source:
Server Name: WINHOSTECN108

Thanks for the come back, and I just checked. No "-1" under the Desktop Modules table "supported features."

Any other ideas?

The errors have returned, so I guess it was not the skins.

Any ideas out there?