Upgrade error and prescan.exe
So you tried to run MOSS 2007 beta 2 install and do an upgrade but you got an error. The error said something like:
Failed to initialize SharePoint Products and Technologies upgrade.
An exception of type Microsoft.SharePoint.PostSetupConfiguration.PostSetupConfigurationTaskException was thrown. Additional exception information: The pre-upgrade scan tool has not yet been run on all servers in the farm. You must run the pre-upgrade scan tool before you can continue with the upgrade process. Run the tool from the following path: c:\program files\common files\Microsoft shared\web server extensions\12\bin\prescan.exe. After you have reviewed any issues found by the tool, you can run psconfig.exe again to continue the upgrade process.
So you took the error message to heart, found the prescan.exe, double clicked on it and then tried to double click on psconfig.exe and nothing happened. Sounds about right to me. What the error message should have told you to do is:
1. Open a cmd prompt
2. Type cd\ and press enter
3. Type cd program files\common files\microsoft shared\web server extensions\12\bin and press enter
4. Now type prescan.exe /c preupgradescanconfig.xml /all and press enter
5. Now when it completes it will give you a log file to review for errors. Assuming you have no errors you can move to the next step. If you do have errors then deal with them. :) Aren't I helpful?
6. Type in psconfigui.exe and press enter.
7. Now go back through the upgrade process hopefully without error this time.
These are the instructions that Microsoft meant to include. :) Hope they help you.