Format Hard Drive

When Windows is reinstalled from the disc (from the "F8" boot window), is the hard drive reformatted automatically? If not how can I achieve this?


Windows Forum Admin
Staff member
Premium Supporter
During the step where you choose which drive/partition to install to, there are advanced options there which will allow you to format a hard drive, create partitions, etc.
I believe you must choose the Custom option in order to get this ability. It looks like this:

More details can be found here:

Always be careful before deleting any partition or formatting a drive. It is near impossible to recover data after these operations have been performed!


Honorable Member
Don't install Windows from the BBS Popup Menu. Disconnect all hard drives except the one that you want to install to, prior to the installation. By doing that, it will not create a boot menu to choose which drive to boot from, which is good, because too often when something goes wrong with one installation, it will effect all others on the boot menu also.

After the installation, reconnect all of those drives and decide which you want to be the primary, and set it as the first boot drive in the BIOS. That way it will always boot to that drive, unless you opt for it to do differently from the BBS Popup Menu.

Thank you for the info Josephur. When I am installing W7 and get to the part that allows you to format the drive (from the Custom option) I notice that I have 2 partitions.
Partition 1: is system reserved at 100MB; and
Partition 2: is 900GB

I want to make sure that the computer is as clean as possible from malware, root kits, viruses etc......
Should I format both parts of the Hard Drive for optimal cleanse?
If so is there any problems that i may be causing for myself for future reference?

Thanks in advance


Windows Forum Admin
Staff member
Premium Supporter
The 100MB partition is created by Windows 7 to store boot and memory tester files I believe. You can safely delete them both, however be aware that when you delete both and then simply click the drive for Windows to install to without manually creating a partition, it most likely will re-create the 100MB paritition. This is no big deal and its best to let it do this anyways. But to answer your question delete both partitions then just point to the drive and let Windows setup take care of creating the new partitions for you. No need to format, simply delete the partitions, this will rid anything that could have been hiding in the boot sector.

Thank you - your help is much appreciated

This website is not affiliated, owned, or endorsed by Microsoft Corporation. It is a member of the Microsoft Partner Program.