i bought a new texture set and when i was uploading the textures some parts didn't worked (left biceps,stomach,right forearm and right foot) the other parts worked fine i tried uploading other type of textures and keep didn't working

Me too. Hate it.

This have happened many times to myself, Check the pixels size of the Photo or image.Close wifi and reopen or reopen browser or of have too,Reinstall.

mine textures fixed automaticaly