NAT DNS not working

[hbsnmyj]

Host: Windows 8.1
Guest: Arch Linux - most recent rolling

The NAT works pretty fine before. However it has been broken since either of a) an update of VirtualBox and b) an accidental lost of my C:\Program Data folder.

On bridge mode it works fine. However on NAT mode, I can ping the DNS server, but could not resolve the address, either through the host dns resolver or the direct connection - it always timed out.

Since under vmware the NAT works pretty well, so I guess it is something related to host and the virtualbox installation. However re-install Virtualbox did not solve the problem.

Any thoughts on the cause of the problem? Thanks.