I recently upgraded to dnn 4.05.01 and since then have received the following error in admin/user accounts

User Accounts

Error: User Accounts is currently unavailable.
DotNetNuke.Services.Exceptions.ModuleLoadException: Arithmetic operation resulted in an overflow. ---> System.OverflowException: Arithmetic operation resulted in an overflow. at Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger(String Value) at Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger(Object Value) at DotNetNuke.Modules.Admin.Users.UserAccounts.BindData(String SearchText, String SearchField) at DotNetNuke.Modules.Admin.Users.UserAccounts.Page_Load(Object sender, EventArgs e) --- End of inner exception stack trace ---

from the event viewer

ModuleId: 357
ModuleDefId: 15
FriendlyName: User Accounts
ModuleControlSource: Admin/Users/Users.ascx
AssemblyVersion: 04.05.01
PortalID: 0
PortalName: Ebred
UserID: 1
UserName: host
ActiveTabID: 42
ActiveTabName: User Accounts
RawURL: /Admin/UserAccounts/tabid/42/Default.aspx
AbsoluteURL: /Default.aspx
AbsoluteURLReferrer:
UserAgent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1)
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
ExceptionGUID: 3d909162-5e81-4fc1-a02a-f397bc9faaf7
InnerException: Arithmetic operation resulted in an overflow.
FileName:
FileLineNumber: 0
FileColumnNumber: 0
Method: Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger
StackTrace:
Message: DotNetNuke.Services.Exceptions.ModuleLoadException: Arithmetic operation resulted in an overflow. ---> System.OverflowException: Arithmetic operation resulted in an overflow. at Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger(String Value) at Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger(Object Value) at DotNetNuke.Modules.Admin.Users.UserAccounts.BindData(String SearchText, String SearchField) at DotNetNuke.Modules.Admin.Users.UserAccounts.Page_Load(Object sender, EventArgs e) --- End of inner exception stack trace ---
Source:
Server Name: SKNET92

and when i post the user account module onto a page i get the following error

Error: User Account is currently unavailable.
DotNetNuke.Services.Exceptions.ModuleLoadException: Object reference not set to an instance of an object. ---> System.NullReferenceException: Object reference not set to an instance of an object. at System.Web.UI.TemplateControl.LoadControl(IWebObjectFactory objectFactory, VirtualPath virtualPath, Type t, Object[] parameters) at System.Web.UI.TemplateControl.LoadControl(Type t, Object[] parameters) at DotNetNuke.UI.Skins.Skin.InjectModule(Control objPane, ModuleInfo objModule, PortalSettings PortalSettings) --- End of inner exception stack trace ---

The upgrade was not done by me but my hosting company and they didn't have any idea how to fix these errors.

I would be greatly appreciated if someone could help.

OK, this seems a bit strange right now, we will be trying again. It appears that at some point we ran a script to update a bunch of tabs to use caching and in that process changed a bunch of admin tabs to use a cache time of 300 seconds. When we removed that from the system, the admin pages work correctly. 

This is somehting that only a lazy hacker like me would try to do in the first place. This appears to have no impact on the older versions of DNN, but impact the way the system handles tabs going forward.

BTW, most pages that submit back to itself to show different views (like XMOD moduels) will not work when caching is turned on for the tab. Let me know if this helps with your issue.