500 - Layout "0" not found errors after 1.1.9 -> 2.x migration

[klompen]

I followed the steps in http://www.ostraining.com/blog/joomla/virtuemart-11-to-version-2 to migrate my test site. Although the front page of the site displays as it should, when I attempt to get to any page which involved VirtueMart I get this error:
Error 500 - Layout "0" not found

I have not been able to find anything helpful by searching this forum.

[klompen]

The balance of the error dialog reads as follows:
"You may not be able to visit this page because of:

an out-of-date bookmark/favourite
a search engine that has an out-of-date listing for this site
a mistyped address
you have no access to this page
The requested resource was not found.
An error has occurred while processing your request.
Please try one of the following pages:

Home Page
If difficulties persist, please contact the System Administrator of this site.

Layout "0" not found"

The environment for this test site is Joomla 1.5.x running on a local Windows 2003 SP2 server under Xampp.

[jenkinhill]

Never seen that before. The official migration procedure in here:  http://forum.virtuemart.net/index.php?topic=95236.0

[klompen]

I've seen that procedure. The steps are the same as the link which I referenced, just packaged differently.

[jenkinhill]

Do you have SEF turned on? Or an .htaccess file that could cause this problem?

[klompen]

Normally, this site does have SEF URLs active and ArtIO's JoomSEF component with the Virtuemart extension. I start with a working VM 1.1.9 site that includes a .htaccess file, which I leave intact.

To double check things, today I completely removed the site, reinstalled using Akeeba's Kickstart program, the ran through the VM upgrade process using the above documents as reference. The steps I took are listed below, in order:

1. Turn off SEF URLs & test site to ensure that it still works.
2. Download & unzip virtuemart 2.0.18a zip file
3. Move media from /components/com_virtuemart/shop_images to new folder at /images/stories/virtuemart
4. Disable Joomla debug option (already disabled)
5. Disable all Virtuemart Joomla modules & plugins
6. Set default language (already set correctly)
7. Rename /components/com_virtuemart and /administrator/components/com_virtuemart folders
8. Install Virtuemart 2.0.18a
9. Install Virtuemart 2.0.18a AIO component
10. Check for incompatible "VM - Search, Virtuemart Product" plugin. NOT FOUND.
11. Preview site: Main site page works, but 500 error is present for any menu items that pull data from Virtuemart
12. Enable database update tools
13. Set up migration. Ran migration 9 times to ensure that all products are migrated. Not possible to tell for certain if all products are migrated because the message space always shows "Max Messages Reached".
14. Preview site: same behavior as #11 above.

At this point, all the disabled VM modules and plug-ins are still installed. Since they are disabled, they should not be in play but I just thought I'd mention the state of the system.

Thanks for the help on this.

[klompen]

I have discovered that this is caused by the following setting:
VirtueMart - Configuration - Templates tab - Layout for your home page: No override

When I change this from "No override" to :"Default" I no longer get the 500 error. Unfortunately, I don't get a useful page that looks like it did when I was running VM 1.1.9, but at least I don't get an error anymore.