Question: Version 4.7.10 on Wordpress 4.6

**Error when selecting Contacts->Manage Groups:**
DataTables warning: table id=DataTables\_Table\_0 - Ajax error. For more information about this error, please see <http://datatables.net/tn/7>

This is a fresh install. The error makes contact group unusable which makes the whole thing unusable.

**Comment from my system admin:**
I've updated the nginx config without any success and also tried updating the PHP query string size limit, again without any success. I would say the next step would be to contact the civicrm maintainers and say that the query string is causing problems. Usually GET query parameters shouldn't exceed more than 255 characters, while the one above is closer to 1300. They should probably be using a POST request instead of GET.

**UPDATE**

Following the instructions from the datatables link above, I compared the demo site to my site.

-The suspect request URL is identical.

-Data transferred / size: demo site 0.05 kb. my site 0.19 kb. This is puzzling since the URL is identical!

-On the demo site request type is json. On my site, it says html.

-Both are GET requests. I also looked at Civi 4.6.21 on WP 4.5.3 and this same request is a POST request. So I guess they changed it to GET.

-Demo site runs Wordpress 4.5.3 and Civi 4.7.11. my site is Wordpress 4.6 and Civi 4.7.10

Answer: 
I have tested the above issue against WP 4.6.1 and CiviCRM 4.7.11. I am running Apache 2.4, php 5.6 and MySQL 5.6. The OS is CentOS 6.

I cannot reproduce this error nor the one mentioned [Ajax Error when trying to view relationships tab](https://civicrm.stackexchange.com/questions/9522/ajax-error-when-trying-to-view-relationships-tab)

I commented in <https://issues.civicrm.org/jira/browse/CRM-19331> about this as well.

I would suspect the issue here is due to either a plugin conflict or something specific to the Hosting Configuration. I am interested if these issues are specific to a host or a specific configuration.

I'd disable all plugins (except CiviCRM) and see if you can trace errors in you apache and php logs. I would also revert to a default theme (CiviCRM demo sites are tested with TwentyThirteen) I'd also look at the CiviCRM logs. The CiviCRM logins should be in the `/civicrm/ConfigAndLog` directory that is stored in the WP upload directory in 4.7

I'd be interested if these issues are specific to a host or a specific configuration.
I did made a test against Wordpress 4.5.3 and Civicrm 4.7.10 - Fresh Copy 

I didn't get any error message as you have reported - may be you should try the same against demo to confirm 

I guess this helps !!!