I have an old site that is built on DNN 3.1.3 that I wanted to slowly upgrade to current version. Problem is I'm running on a totally different platform. I'm running Win7 64bit with SQL2005. I finally got the site to come up but there is a major issue with modules posting the following: Multiple controls with the same ID 'ctr' were found. FindControl requires that controls have unique IDs. I read somewhere that you can't jump to SQL2005. Is this true? I tried looking for MSDE 2000 Re. A but it looks like MS took it off their site.

I would start by looking at the modules on your site and see if there are some that require updating to run on the newer version of DotNetNuke.  If you log in as admin or host and look in the Event Log, you will see more details regarding the errors.  Actually, if you are logged in as host or admin, more details will be shown on the pages.

Also, you did not say to which version of DotNetNuke you are upgrading.  There is a preferred sequence, and it is not recommended that you make the leap directly from 3.1.3 to 5.x.  So, you will probably want to go back to 3.1.3 and then start upgrading in steps.  You will find some good suggestions regarding the sequence of upgrades at Mitchel Sellers' Blog (mitchelsellers.com) and Will Strohl's blog (willstrohl.com).

There should not be any problem upgrading your SQL Server.

Hey Joseph, I intended to upgrade as you suggested, slowly.... But problem is I can't log into the site. So I'm having to go to Portals > _default > logs > Exception.xml.resources and look at it with notepad.

I'm having a hard time trying to decypher it though. (i.e.)
DotNetNuke.Services.Exceptions.PageLoadException: Multiple controls with the same ID 'ctr' were found. FindControl requires that controls have unique IDs. ---> System.Web.HttpException: Multiple controls with the same ID 'ctr' were found. FindControl requires that controls have unique IDs.
at System.Web.UI.Control.FillNamedControlsTable(Control namingContainer, ControlCollection controls)
at System.Web.UI.Control.FillNamedControlsTable(Control namingContainer, ControlCollection controls)
at System.Web.UI.Control.EnsureNamedControlsTable()
at System.Web.UI.Control.FindControl(String id, Int32 pathOffset)
at System.Web.UI.Control.FindControl(String id)
at DotNetNuke.UI.Skins.Skin.Page_Init(Object sender, EventArgs e) in D:\AWDNN313\admin\Skins\Skin.vb:line 178
at System.Web.UI.Control.OnInit(EventArgs e)
at System.Web.UI.UserControl.OnInit(EventArgs e)
at System.Web.UI.Control.InitRecursive(Control namingContainer)
at System.Web.UI.Control.AddedControl(Control control, Int32 index)
at System.Web.UI.ControlCollection.Add(Control child)
at DotNetNuke.Framework.CDefault.Page_Init(Object sender, EventArgs e) in D:\AWDNN313\Default.aspx.vb:line 199
at System.Web.UI.Control.OnInit(EventArgs e)
at DotNetNuke.Framework.PageBase.OnInit(EventArgs e) in D:\AWDNN313\components\Shared\PageBase.vb:line 97
at System.Web.UI.Control.InitRecursive(Control namingContainer)
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
--- End of inner exception stack trace ---

Is the error that you reported still with a 3.1.3 installation and the "only" change that you have made is the switch to SQL Server 2005?

The other thing that you might check is that (assuming this is 3.1.3) your web site is configured for ASP.NET 1.x.  I believe that 2.x was supported only for DotNetNuke 4.x.

WOw, finally figured it out,.... with some help It had to do with me not having IIS6 Metabase installed. here's the article that helped me figure it out.
http://learn.iis.net/page.aspx/472/how-to-install-aspnet-11-with-iis7-on-vista-and-windows-2008/

Thanks for your help JOseph