This page has a few general Windows-related issues that I've come across. I rarely use Windows these days hence the small size of this page :)
Can't ping 127.0.0.1 (or any other IP), error "General Failure"
I came across an issue where I was able to get an IP from DHCP and what looked like a working network configuration, however was still unable to ping out. Even pinging 127.0.0.1 gave "General Failure" errors.
To fix this, I ran the following at the Windows command prompt:
netsh int ip reset reset.txt netsh winsock reset
This essentially resets the TCP/IP stack (which was likely corrupted in my case). After rebooting, networking came back fine.
Find DN for all users (LDAP)
Open a command prompt. Enter:
dsquery user > c:\dn.txt