hosts file stopped working unexpectedly

Hi lads!

Yesterday I updated Win7 x86 to SP1 and today found out that all my local virtual hosts has stopped working.

First, I checked apache service - it was ok, but I restarted it.

Then I tried to ping one of local domain names:

Code:

C:\Users\evgeny g likov>ping aaa1
Ping request could not find host aaa1. Please check the name and try again.

I was thinking, SP1 setup just wiped all additions out of hosts file, but no:

Code:

127.0.0.1    localhost
127.0.0.1    aaa1
127.0.0.1    aaa2
127.0.0.1    aaa3
127.0.0.1    aaa4
127.0.0.1    aaa5
127.0.0.1    bin.likov.spb.ru.local
127.0.0.1    likov.spb.ru.local
127.0.0.1    mycodb.ru.local
127.0.0.1    votdermo.ru.local

Then I tried:
- re-create hosts file
- flush dns
- disable antivirus (nod32 v4)
- reboot system
- disable IPv6 on the main interface

Do you have any ideas?

Thank, Seth500. Access to hosts file is granted to SYSTEM and Administrators.

After reboot hosts is not working again. DNS Client is stopped.

Solved again, I think.

I know nothing about reasons, just magika. After half of hour of checking parameters of Windows, I granted special access to file hosts for NETWORK SERVICE user. Then I run DNS Client service.

Now it work.

Still ok.