e-mail translation prestashop 1.5 backoffice when translating i get a 500 server error

[r2get]

Hello,

 

Im having a error with my curent prestashop 1.5.2 installation

 

I have 2 languages dutch and english.

 

In the backoffice email translation (where you can edit the template and the translations)

 

when i edit a field and update (both save & save and stay) I get a internal 500 server error.

 

every thing is cmodded 777

 

I also had this with my pdf translations but i had to ad a nl.php language file in the themes PDF folder.

 

After that i didnt got the error on the pdf translations

 

how can i fix this for my email translations?