Images generation returns error 500

[HaCos]

Hello i am trying to regenerate images for all my products (there more than 2.000 products where each one has 2-5 images). I select one image type per time, i managed to regenerate most of my images but when i am trying the last 2 img types (the bigger ones 800x800 & 1000x1000), i get an error 500 after a while... I opened server logs and i found the following error recording: 

[Wed Oct 29 21:33:35 2014] [warn] (104)Connection reset by peer: mod_fcgid: error reading data from FastCGI server, referer: ....

[Wed Oct 29 21:33:35 2014] [error] Premature end of script headers: index.php, referer: ....

Has anyone resolved any similar issue?

 

Thanks in advance for any help.

 

Regards,

C