I am getting the below error while filing a tax return: > X0000-005 - The XML data has failed schema validation. When I try to resubmit my return I get the same error.

This is a known issue that began about mid-afternoon today (Sunday.)   Several users are reporting they have been impacted by rejection error X0000-005 .     We have reported it to a TurboTax Moderator, but they may not be able to investigate it until during the day on Monday.   And it may or may not be fixed on Monday.

Hold off for now, and something may reset in the next 24 hours that lets you efile soon.  Or at least more info should be coming on Monday.

Give them a chance to work on it.   It may or may not be fixed immediately. The filing deadline is still 24 days away. I personally wouldn't print and mail unless it approached the deadline with no fix. If it's going to take them a while to fix, they usually put out a containment FAQ with more info and possibly a place to sign up for email notifications.

Or if you want to phone Support on Monday here's how. 

Hours are 5AM-9PM Pacific (8AM-12 Midnight Eastern) 7 days.

FAQ: What is the TurboTax phone number?
https://ttlc.intuit.com/community/using-turbotax/help/what-is-the-turbotax-phone-number/00/25632

Or use this contact form:
https://support.turbotax.intuit.com/contact

Thanks for your post,  I'm on my 8th attempt (7 different iterations yesterday). Now I'll sit tight for a few days and wait to see if the cause resolve's itself.

When I asked Help within the program it indicated the cause was most likely an out of place , or . or something like that and could not be resolved so file by mail. Didn't think that was an  acceptable answer so I'm gad I waited and found this forum.

I am hitting same issue, for me it started from midnight Sunday

Has this issue been resolved? It's now Wednesday.

HA Korn