Eclipse Mars - eclipse.org.equinox.p2.core.provisionexception

Question

I installed eclipse mars in my windows 8.1 Pro pc and its update site as below

Mars

http://download.eclipse.org/releases/mars

The Eclipse Project Updates

http://download.eclipse.org/eclipse/updates/4.5

but when i try to reload, it raises following

No repository found at http://download.eclipse.org/releases/mars.
eclipse.org.equinox.p2.core.ProvisionException

i tried following solutions but none works for me.

1. added -Djava.net.preferIPv4Stack=true in eclipse.ini

2. changed my to manual

3. Unchecked "contact all software sites during install to find required software" option under install new software

Note : Firewall is disabled

Answer 1

This is know bug see Bug 470900 - Eclipse Mars repository for EPP causing problems and Bug 471528 - No repository found
Just delete delete the following:
$HOME/.eclipse/org.eclipse.oomph.p2/cache directory!

in windows:

C:\Users\yourusername\.eclipse\org.eclipse.oomph.p2\cache