I have just upgraded from 6.15 > 6.23 and have discovered i can no longer create a new parent site from a newly exported template. I can however create a new site from the 'blank' DNN template. 

HOWEVER, after making a template from this NEW BLANK site, it can no longer reproduce itself... in other words, I get the same exact error as with any other template I create after the EXPORT AS TEMPLATE process.

"newblanktemplate.template is not a valid Site Template File. 

Validation Results

The element 'tab' has invalid child element 'content'. List of possible elements expected: 'containersrc, Terms, startdate, skinsrc, permanentredirect, issecure, keywords, KeyID, name, description, iconfile, disabled, title, refreshinterval, defaultLanguageTab, url, tabpermissions, pageheadtext, panes, tabsettings, moduleID, iconfilelarge, sitemappriority, cultureCode, visible, tabtype, enddate, parent'.

I've replaced all the template.xsd, etc files from a NEW installation file set (6.2.3) and still get nowhere.

This is a complete show stopper for us on production!

Ideas? (beside going back to 6.15?)

Sebastian, what do you think would cause this behavior...

In the DNN installation I'm having the 'new' portal template issues with, I moved the suspect template to another DNN installation - which is an identical 6.1.4 version and nearly identical number of parent portals in it. The second DNN install creates the parent portal from the template as expected, with all 84 tabs.

But the first (problem) DNN install will not create more than the 'home' page from the same template. It doesn't create all the Admin pages, nor any of the other public pages.

I've checked that there aren't any odd characters for tab names, etc.
I've overwritten ALL the DNN core pages/files from both the downloaded dnn installation and upgrade versions and from the DNN install that WILL create the parent portal from the template.

I'm stumped. It seems that I have a DB issue, since the files and template seem to be working.

Your thoughts?

I've fixed the template import by modifying the template as you suggest. along with a couple other lines. The template now works fine - and it still doesn't.

CASE:
I have two distinct dnn 6.2.3 installs (A) & (B) [both upgrades from today with 94 sites in each] and a single template (1) that was created on DNN (A)

• Template (1) creates a perfect parent site (all 84 pages) on DNN B
• Template (1) creates 0 pages (out of 84) on DNN A - NOT what we want.

What or where should I start looking for something wrong?
tabs table for DNN (A)?