LiveUpdate Administrator 2.3.4 and Protection Engine 7.02 still use 512 bit key lengths and will therefore not support the new 1024 bit encrypted transport introduced by the above Microsoft Windows updates.
The current Protection engine releases do support the new required 1024 bit key length.
Upgrade your Protection Engine and Liveupdate Adminstrator to a more recent release.
Should this not be immediately possible, review Microsoft Security Bulletin MS15-055 which explains how to enable 512 bit key encryption after the Windows update.