cannot save connection

[ATTACH=JSON]{“data-align”:“none”,“data-size”:“full”,“title”:“2018-09-25 23_57_58-ScriptCase __ Production Environment.jpg”,“data-attachmentid”:84886}[/ATTACH]any ideas what could cause not being able to save connection setting on the production server ?
App shows spinning icon forever and nevers save settings

2018-09-25 23_57_58-ScriptCase __ Production Environment.jpg

could be write permission to the _lib / conf folder.

thanks but, my _LIB folder has all files and subfolders set to 755
I have more than one project on the same server and just tested another project. there was no problem saving connection settings.
Permissions are set exactly the same way for both projects.

tested locally on WAMP and the same issue appears. Cannot save connection.

I have the same problem when I send to production