Hey all,
My site seems to have somehow stuck itself on the Install/UpgradeWizard.aspx page, though I did nothing to initiate an upgrade. My current version is 07.02.01 and it is attempting to upgrade me to version 07.02.02. Attempting to navigate to any page on any of the 5 portals I have installed will redirect me to the Install/UpgradeWizard.aspx. Attempting to run the Upgrade results in the following error after noting that the Updating Database step is complete: 

XX:XX Minutes | 50% ERROR occured - {0}: Attempted to divide by zero.

The Minutes remaining counter seems to just count infinitely upward at this point. The upgradestat.log.resources.txt file contains only the following lines upon failing to upgrade:

{"progress":21,"details":"Upgrading Application","check0":"Running","check1":"NotStarted"}
{"progress":50,"details":"ERROR occured - {0}: Attempted to divide by zero.","check0":"Done","check1":"Running"}

The InstallerLog file contains nothing of consequence:

12/03/2014 17:16:32 [INFO] DotNetNuke.Services.Upgrade.Internals.Steps.BaseInstallationStep Upgrading Application

The log.resources file for the day lists the following error repetitively:

2014-12-03 12:16:33,385 [MACHINENAME][Thread:14][ERROR] DotNetNuke.Services.Exceptions.Exceptions - System.IndexOutOfRangeException: Custom404TabId

   at System.Data.SqlClient.SqlDataReader.GetOrdinal(String name)

   at System.Data.SqlClient.SqlDataReader.get_Item(String name)

   at DotNetNuke.Entities.Portals.PortalInfo.Fill(IDataReader dr)

   at DotNetNuke.Common.Utilities.CBO.FillObjectFromReader(Object objObject, IDataReader dr)

I doubt this error has anything to do with the Upgrade loop, it may be just be a missing setting on one of my Portals, though I can't actually access anything to make sure. 

Can anyone offer any help? Even just where/how to disable the Upgrade process entirely would be of immense help as again, I don't even want to upgrade.

Sebastian,

Thanks for the reply. I have no backup prior to this upgrade loop as I did not initiate it, it just came out of the blue. I don't want to upgrade at all. I have tried replacing the Install folder in my site's directory with a fresh copy to no avail. 

What I would be more concerned about was making sure that no one has access to you site via FTP to hack the bin folder - if for example a hacker was trying to force in a 'altered' version of dotnetnuke.dll - that could trigger the undate engine if it saw a different version number after the hack.

If for example - only the version of dotnetnuke.dll file had been changed
 - then the site would go into an upgrade loop - because the rest of the elements of the site would never update to the new version - they would stay at the current version.

Westa