Failed to save environment to (80070057) when deploying Windows 10

Hi all,

When I try to deploy Windows 10 using MDT 2013 Update 2, I get the error "Failed to save environment to (80070057)" when starting task sequence engine. I have tried changing ImageOSVer as suggested here:

https://tomasrk.wordpress.com/2015/04/16/sccm-2012-r2-error-0x80070057-unable-to-apply-os-target-destination-not-found/

But no hope. I can deploy Windows 7 no problems. I'd love to upload unattended, smssts.log, and bdd.log files, but am unsure how to do that on this forum (this is the first time I've asked on technet myself)