Made mistake of upgrading to the latest version of DNN directly without trying first on a backup copy. Whole website at www.woodstockct.gov is down. Appears to be that the older version of DNN stuff aggregator that was installed no longer works. 

Purchased latest aggregator but am now unable to install, as module definitions doesn't work - don't have option to install new module from module menu. instead I just see this error

HELP!!!!!!!!!!!!!!!!!.

Error: Module Definitions is currently unavailable.
DotNetNuke.Services.Exceptions.ModuleLoadException: E:\clnts\www.WoodstockCT.gov\Admin\ModuleDefinitions\ModuleDefinitions.ascx.vb(61): error BC30311: Value of type 'String' cannot be converted to 'System.Version'. ---|> System.Web.HttpCompileException: E:\clnts\www.WoodstockCT.gov\Admin\ModuleDefinitions\ModuleDefinitions.ascx.vb(61): error BC30311: Value of type 'String' cannot be converted to 'System.Version'. 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.Compilation.BuildManager.GetVPathBuildResult(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.ControlUtilities.LoadControl[T](TemplateControl containerControl, String ControlSrc) at DotNetNuke.UI.Modules.ModuleHost.LoadModuleControl() --- End of inner exception stack trace ---

Thanks for your reply Sebastian!   I am desperate and clearly do not know what the heck I am doing. 

I cannot see that choice under either  Host or Admin.  I CAN get into file manager under Admin - is it possible to unzip and install the module there?  If so, where do I put it?

All I see under for options under HOST are:  host settings, portal, module def (getting error there), file manager, vendors, SQL, schedule, languages, search, listrs, super users and skins and marketplace..

All I see for options under ADMIN are: site settings, pages, security roles, user accounts, vendors, site log, bulk email, file manager, recycle bin, event viewer, skins, language, site wizard, authentication and solutions explorer
arrrrrrrrrrrrrrgh!

Can you help me figure out where to FIND the Aggregator .dll to try deleting it? I don't know where the bin directory is - I don't see anything that looks like it might be that module in file manager.