Just a shot in the dark, but if you're going to reinstall, I'd first try [creating and] logging into another admin account to see if you can edit permissions or just delete the file and make a new one (it's just a few lines of text at default, which is what you'll wind up with if you reinstall anyway). You may also be able to delete it using a bootable CD if you have one.
Try this, it resets all the Security Settings in Windows 7 to the defaults.
Start Menu - type in Search box -> CMD, then at the top - Right Click on - RUN AS ADMIN
Type or Copy and Paste this at the prompt :
secedit /configure /cfg %windir%\inf\defltbase.inf /db defltbase.sdb /verbose
Hit Enter.
Since you say you can easily restore if things go bad..........
Ctrl + Shift + left mouse button
You can provoke an elevation of your privileges (when clicking on items which only require a single mouse click) such as:
- Pinned Taskbar items.
- Start Menu items.
- Start Menu Search results.
Method 1.
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You need to be logged in as Administrator for this method.
To take control of your system's hosts file, go to the properties, select Security tab, click on Advanced button in the bottom of the dialog box.
In the second dialog box "Advanced Security Settings for hosts" go to the Owner tab press "Edit" button.
You will see that the System account is the default owner of this file. Now take ownership of the file.
After taking ownership of the file you can change the permissions for any user listed there. You can also add new user account or delete existing accounts from the permissons dialog box. Set the permissions to your satisfaction and close all the dialog boxes by clicking OK buttons.
Method 2.
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etc/hosts file is just a text file which can be modified easily. I am including the contents of the hosts file from my windows 7 home premium system.
# Copyright (c) 1993-2009 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
# 102.54.94.97 rhino.acme.com # source server
# 38.25.63.10 x.acme.com # x client host
# localhost name resolution is handled within DNS itself.
# 127.0.0.1 localhost
# ::1 localhost
If your hosts file is not working you may create a new text file named "hosts" without extension and copy the above contents in to the file and save it. You can replace your system's hosts file with this file.
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