NEW RECOMMENDED SOLUTION (EDITED) : Open AVA/Binaries/XIGNCODE.USA folder then run xm.exe as Adminstrator, Wait for 1 minute then run AVA from AVA.exe which is in Binaries folder Xigncode should update normally when it finish updating close it then run it from NWZLauncher then it should work like before.
If this failed then try the solutions below.
1. Completely close your firewall.
2. Close your Anti-virus Completely with all of its functions.
3. Close any Program that isn't System involved one.
4. Open 'Task Manager' >> 'Processes' and close both processes with that name "netsession_win.exe" and close any useless process.
5. Click on Start Menu >> Search for "Run" then write 'msconfig'
it will be looking like that :
then Choose "Startup" tab and Un-check all the programs you don't need.