problem with image upload

What version of 68 Classifieds are you running?
v4.1.9 Developer

What template are you using?
original, also NeoBlack2


so, here are my problem:

i've installed the system one a year ago, without major problems. the go live of the site was never, because i had no time to complete the customizing

so, now i take a look as my old installation and want's to complete the customizing now

if i try to placed an ad, i will hang at the step of picture upload. i choose an image and want to upload it. but the systems message is:

Process Log

1. Upload failed: large.jpg :error:

but i wonder - the image is transfered to the server correctly! ... i try it with many images, the format and size are correct - and all the images are on the server now, but in the upload process the systems message are tell mir, that is an error occured. but: error: ... its empty. no sign what error is occured. also in the serverlogs i find no error. and the images are all in the right server folder (/photos).

can anybody help me please?

thanks! ... and sorry for bad english

regards,
tom