Okay, I am close to having a lean and mean log file; thanks, John and Mitchel, for helping me find and remove the damn Sixxac remnant that was triggering errors; thanks to everyone else for helping me with the "-1" errors that were cluttering up the log.

I am only getting errors now when someone visits the forums.

AssemblyVersion: 04.05.03
PortalID: 0
UserID: 18
ActiveTabID: 56
ActiveTabName: Forums
RawURL: /Forums/tabid/56/Default.aspx
AbsoluteURL: /Default.aspx
UserAgent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR 1.1.4322; .NET CLR 3.0.04506.30)
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
InnerException: Object cannot be cast from DBNull to other types.
FileName:
FileLineNumber: 0
FileColumnNumber: 0
Method: System.DBNull.System.IConvertible.ToInt32
StackTrace:
Message: System.InvalidCastException: Object cannot be cast from DBNull to other types.at System.DBNull.System.IConvertible.ToInt32(IformatProvider provider)at System.Convert.ToInt32(Object value)at DotNetNuke.Modules.Forum.ForumController.ModuleGetAll(Int32 PortalID, String Type)

I get these every 10 seconds, it seems, but perhaps that's the click-pattern of the users who were triggering the error.  :)  Any ideas?

leupold wrote it looks like an invalid entry in module table. clear recycle bin and check database table Modules.

Danke, Leupold; I deleted the recyle bin (for the first time since I started...never played with it, or saw it there before, for that matter) :)  I checked the 'module' tables, but not quite sure what I am looking for...wouldn't know an invalid entry from a valid entry.  :)

I thought perhaps it was due to a user posting a Yahoo news release, which had a ton of span tags and localized info from Yahoo that triggers their word tag pop-up thingies, but even after deleting all those posts, I can still trigger the errors just by visiting the page.

Think installing the same forum version 'upgrade' file over the top might fix the problem? I hate to lose the current groups I created (the posts are immaterial), but even without an ability to export these data, I am willing to try anything to stop the errors from filing my log.