I've built a wordpress website on my mamp localhost, and subsequently uploaded it to a web hosting service.
Since I've uploaded it I cannot upload images via the wordpress 'add media' section. I temporarily change the 'uploads' permissions to 777 and it solved the problem.
I know 777 isn't best practise so I changed it back to 755 and the error has reoccurred.
Is this something to do with the admin user and password I originally set up for wordpress on my localhost versus the ftp user which I created and used to upload the site to the web hosting service?
Does the ftp user own the files - therefore stopping the wordpress admin user from uploading files?
Thanks
chown -R username:groupname
your apache user/group. – rnevius