http://www.lavahelp.com/articles/v6/04/05/2201.html
QUOTE
Attention Ad-Aware users
Ad-Aware has decided to include a new detection when scanning the HOSTS file. This now creates a "Bad hosts file entry" in the log file generated at the end of a scan. The best thing to do is to place a check in each entry, right-click and select: "Add selection to ignorelist". Otherwise if you let AWW "fix" these items it will trash the HOSTS file! Even if you have it "locked" by [example] SpywareBlaster or Winpatrol. It does not return the attributes and renames the HOSTS file incorrectly to hosts. [more info]
SYMPTOM
During an Ad-aware scan, several entries are listed in the scan results indicating that a "Possible Hostsfile Hijack" is taking place. The entries listed may be created by a known source, such as a pre-assembled hosts file designed to help prevent items such as trackware from being successfully downloaded, or by a program designed to use the hosts file in its normal operation.
CAUSE
Some of the entries included in these pre-assembled hosts file lists and by some programs which use the hosts file are also used by items in Ad-aware's detection. Since Ad-aware cannot determine the source of the entry in the hosts file, and that the entry could possibly be created by an item in Ad-aware's detection, the item in the hosts file is listed.
RESOLUTION
If the system is using a hosts file which has been pre-assembled, or is running a program which utilizes the hosts file, and the listing is related to these reasons, add the items listed by Ad-aware to the ignorelist to prevent their listings during future scans.
Ad-Aware has decided to include a new detection when scanning the HOSTS file. This now creates a "Bad hosts file entry" in the log file generated at the end of a scan. The best thing to do is to place a check in each entry, right-click and select: "Add selection to ignorelist". Otherwise if you let AWW "fix" these items it will trash the HOSTS file! Even if you have it "locked" by [example] SpywareBlaster or Winpatrol. It does not return the attributes and renames the HOSTS file incorrectly to hosts. [more info]
SYMPTOM
During an Ad-aware scan, several entries are listed in the scan results indicating that a "Possible Hostsfile Hijack" is taking place. The entries listed may be created by a known source, such as a pre-assembled hosts file designed to help prevent items such as trackware from being successfully downloaded, or by a program designed to use the hosts file in its normal operation.
CAUSE
Some of the entries included in these pre-assembled hosts file lists and by some programs which use the hosts file are also used by items in Ad-aware's detection. Since Ad-aware cannot determine the source of the entry in the hosts file, and that the entry could possibly be created by an item in Ad-aware's detection, the item in the hosts file is listed.
RESOLUTION
If the system is using a hosts file which has been pre-assembled, or is running a program which utilizes the hosts file, and the listing is related to these reasons, add the items listed by Ad-aware to the ignorelist to prevent their listings during future scans.