Thanks for mention it here. ICSdroid uses the http lib of Android.
302: Moved Temporarily not working
I have a synced calendar for school using a system called Edumate. Attempting to log in with ICSDroid doesn’t redirect correctly, and produced a ‘302 Moved Temporarily’ toast. Visiting the ICS file in Chrome on my mac downloads it correctly.
Which ICSdroid version are you using?
Can you provide the URL?