Adding a bit of information. I don't know if this helps.
After the error occured, Ajax was turned off, so I went to Host Settings to turn it back on and received this error:
ModuleId: 327
ModuleDefId: 72
FriendlyName: Host Settings
ModuleControlSource: admin/Host/HostSettings.ascx
AssemblyVersion: 04.08.00
PortalID: 0
PortalName:
UserID: 1
UserName: host
ActiveTabID: 16
ActiveTabName: Host Settings
RawURL: /Host/Host Settings/tabid/16/portalid/0/Default.aspx
AbsoluteURL: /Default.aspx
AbsoluteURLReferrer: http://mysite.com/Host/Portals/tabid/17/portalid/0/Default.aspx
UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.2; en-US; rv:1.8.1.11) Gecko/20071127 Firefox/2.0.0.3;MEGAUPLOAD 1.0
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
ExceptionGUID: 82733dec-80c6-48bc-ad63-e6e301633712
InnerException: External component has thrown an exception.
FileName:
FileLineNumber: 0
FileColumnNumber: 0
Method: System.Web.Compilation.AssemblyBuilder.Compile
StackTrace:
Message: DotNetNuke.Services.Exceptions.ModuleLoadException: External component has thrown an exception. ---> System.Exception: External component has thrown an exception. ---> System.Web.HttpCompileException: External component has thrown an exception. at System.Web.Compilation.AssemblyBuilder.Compile() at System.Web.Compilation.BuildProvidersCompiler.PerformBuild() at System.Web.Compilation.BuildManager.CompileWebFile(VirtualPath virtualPath) at System.Web.Compilation.BuildManager.GetVPathBuildResultInternal(VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile) at System.Web.Compilation.BuildManager.GetVPathBuildResultWithNoAssert(HttpContext context, VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile) at System.Web.UI.BaseTemplateParser.GetReferencedType(VirtualPath virtualPath, Boolean allowNoCompile) at System.Web.UI.BaseTemplateParser.GetUserControlType(VirtualPath virtualPath) at System.Web.UI.MainTagNameToTypeMapper.ProcessUserControlRegistration(UserControlRegisterEntry ucRegisterEntry) at System.Web.UI.BaseTemplateParser.ProcessDirective(String directiveName, IDictionary directive) at System.Web.UI.TemplateControlParser.ProcessDirective(String directiveName, IDictionary directive) at System.Web.UI.TemplateParser.ParseStringInternal(String text, Encoding fileEncoding) --- End of inner exception stack trace --- at System.Web.UI.TemplateParser.ProcessException(Exception ex) at System.Web.UI.TemplateParser.ParseStringInternal(String text, Encoding fileEncoding) at System.Web.UI.TemplateParser.ParseString(String text, VirtualPath virtualPath, Encoding fileEncoding) at System.Web.UI.TemplateParser.ParseFile(String physicalPath, VirtualPath virtualPath) at System.Web.UI.TemplateParser.ParseInternal() at System.Web.UI.TemplateParser.Parse() at System.Web.Compilation.BaseTemplateBuildProvider.get_CodeCompilerType() at System.Web.Compilation.BuildProvider.GetCompilerTypeFromBuildProvider(BuildProvider buildProvider) at System.Web.Compilation.BuildProvidersCompiler.ProcessBuildProviders() at System.Web.Compilation.BuildProvidersCompiler.PerformBuild() at System.Web.Compilation.BuildManager.CompileWebFile(VirtualPath virtualPath) at System.Web.Compilation.BuildManager.GetVPathBuildResultInternal(VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile) at System.Web.Compilation.BuildManager.GetVPathBuildResultWithNoAssert(HttpContext context, VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile) at System.Web.UI.TemplateControl.LoadControl(VirtualPath virtualPath) at System.Web.UI.TemplateControl.LoadControl(String virtualPath) at DotNetNuke.UI.Skins.Skin.InjectModule(Control objPane, ModuleInfo objModule, PortalSettings PortalSettings) --- End of inner exception stack trace ---