The server was unable to save the form at this time. Please try again - tried the trust standards...

Question

2013 standard sharepoint server.  Content DBs were on a Trial enterprise server and copied over to standard server. All was good on trial server.
there are 8 sites on server, 2 of the sites cannot create or edit items, they get "The server was unable to save the form at this time. Please try again"
googling around i tried everything. restarted search host controller, checked ram usage (8gb free), manage content types, iisresets, edit the web.config file ( add things for ram, search host, etc), no alternate access mappings, .net HTTP activation, rebooted
server... I'm sure i missed some.
The server is new install, all but the August HF CUs. Trial server the content DBs came from is at same level.
It is not a server level issue as the other 6 sites are fine. its something with just 2 sites.
kinda stuck here...
Thanks,
   Scott<-

Answer 1

With the USL Logs were hard to track down what was happening, though I think it was too do with /_vti_bin/client.svc/ProcessQuery.
I did the Enable/Disable Anonymous Access on the Directory with no luck.
Brought up Fiddler and Saw that I was getting 401 and 500 Errors on
GET http://team.intranet.eandm.com/it/_vti_bin/client.svc/ProcessQuery HTTP/1.1
So it had something to do with Permissions. I checked the Authentication and the sites that worked had Forms Auth Enabled, and the ones that didn't, didn't have forms Auth enabled.  Enabling it manually was no go.
I then went though the web.config on the working and non-working sites and there were some differences.   The Authentication was Forms on the working site, Windows on the nonworking. There was many things not present. httpModules section was missing,
Many of the Microsoft Identity /Authentication lines etc. 
So I Basically took the web.config from the working site and copied it to the non-working site preserving the following line from the original web.config:
<machineKey validationKey="{key}" decryptionKey="{key}" validation="{hash}" />
After that I had Security Issues, Though I think this was Caused by the July 2014 CU making everything use the Microsoft Identity parts, where as the server I was porting form had the sites created before the July 2014 CU. (though both were at the same level)
Even though all of the users were present in the site security, I had to Drop and re-add them to every site/and list with special Perms. 
With the Security Fixed, I no longer received the Error "The server was unable to save the form at this time. Please try again"
Knock on wood its all functioning fine.