I was trying to download ava by using Aeria Ignite then it download to 2/3 10% then stops and says "Error Akamai netsession client not installed"
Did you manually delete it or something?
As far as i know Ignite installations do install Akamai aswell.
Ignite uses it to enhance the download speed and i assume it won't work if it misses.
Try reinstalling Ignite if the problem is still present.