Create new quote does but remains in the create page

[splaisan]

clicking on ‘Submit’ creates a new quote record silently but stays on the submit page instead of jumping in the newly created quote page to fill it. Same happens after clicking Submit for a new Invoice.
Could this be automated so that the user is immediately brought to the new page to proceed?
Or at least close the ‘Create page’ and return to the home page
I created 5 quotes before figuring out I was creating duplicates.

the demo site does what I ask, there must be a problem with my settings/configuration
(running PHP5.5.29 OSX10.10 IP1.4.4)
Thanks for the great product, I am almost addicted

[Kovah]

Hello,
this problem occurs if your system returns an error instead of the correct quote / invoice. Please check your web server error logs.

[splaisan]

I created three quotes from the Submit page

cat /var/log/apache2/access_log

::1 - - [29/Dec/2015:16:22:03 +0100] "GET /InvoicePlane_v1.4.4/quotes/ajax/modal_create_quote HTTP/1.1" 200 124725
::1 - - [29/Dec/2015:16:22:08 +0100] "POST /InvoicePlane_v1.4.4/quotes/ajax/create HTTP/1.1" 500 1767
::1 - - [29/Dec/2015:16:28:24 +0100] "POST /InvoicePlane_v1.4.4/quotes/ajax/create HTTP/1.1" 500 1767
::1 - - [29/Dec/2015:16:28:36 +0100] "POST /InvoicePlane_v1.4.4/quotes/ajax/create HTTP/1.1" 500 1767

nothing in cat /var/log/apache2/error_log, cat /var/log/apache2/invoiceplane-error.log , cat /var/log/apache2/invoiceplane-access.log at these times

[splaisan]

problem got fixed together with Discount left empty leads to error at save
the problem was with mysql strict modes (http://stackoverflow.com/questions/18762308/how-to-get-rid-of-strict-sql-mode-in-mysql)