It seems like you have an early version of ovirt-4.0, if you'll update your version it might solve some of your problems (such as the exception in the screenshot). soon, the size and format will be deduced from the image as well, so many things will be clearer.If you want to stay with your version, you'll need to do the following steps in order to upload the file:- At the engine's host, yum install ovirt-imageio-proxy- Then, run engine-setup.- Add the engine's CA to the Authorities list in your browser. (you can download it from https://%your_engine%/ovirt-engine/services/pki- resource?resource=ca- certificate&format=X509-PEM-CA ) regarding the size- you can choose a bigger size than the original file's size.Hope that works out for you!