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Windows 7: Should I reformat Windows partition before re-installing?

15 Nov 2016   #1

Win 7 64-bit Home Premium
Should I reformat Windows partition before re-installing?

I have Win 7 Home Premium SP1 on Dell Inspiron 17R 5720, 4 GB RAM.

I have Windows and programs on C: partition. Data is on E: partition.

I want to do a clean re-install of Win 7 SP1, and leave all the data on E:

My question is: Should I format the C: partition before re-install?

I saw this post by Alejandro85 here:

Delete or format C drive when reinstalling Windows?

Quote   Quote: Originally Posted by Alejandro85 View Post
There is no need to delete (or even format) any partition to reinstall Windows.
My problem is that I'm so old I remember when disks used to frequently develop bad sectors during use. These bad sectors were marked in the FAT during formatting, so that they would not be used by DOS.

Is this no longer true? :)



My System SpecsSystem Spec
15 Nov 2016   #2

Win-7-Pro64bit 7-H-Prem-64bit

Personally I would and always do clean or clean all the drive before fresh installation.
You should have your personal data on a removable device to transfer it back afterwards.

Use free mini tool to run a surface test for bad sectors
Best Free Partition Manager for Windows | MiniTool Partition Free
My System SpecsSystem Spec
15 Nov 2016   #3

Windows 7 HP 64

This is very IMPORTANT: Disconnect ALL other drives, leaving on only the target disk that you want to have Windows installed.
If you don't do it, you may end with windows installed on one disk and the boot loader on another.

As it is a OEM the main drive may have Dell services partitions and the factory recover partition.
The laptop probably came with Win 8. Did you do the factory recover disks?

I would only format the (big) Windows partition and reinstall win 7 on it.
My System SpecsSystem Spec

15 Nov 2016   #4

Windows 7 Pro x64 Windows 10 Pro x64

Yes, format your install partition.

If the drive has bad sectors, I would get a new one before re installing windows.


SSD 850 PRO 2.5" SATA III 256GB Memory & Storage - MZ-7KE256BW | Samsung US

SSD 750 EVO 2.5 SATA 500GB Memory & Storage - MZ-750500BW | Samsung US

Chose custom when you get to this window to choose a partition to format.

Clean Install Windows 7

Attached Images
Should I reformat Windows partition before re-installing?-capture.jpg 
My System SpecsSystem Spec
15 Nov 2016   #5

Windows 7 Pro 64 bit

While not strictly necessary it is always a good idea to format the partition. This is normally done as part of the install process.
Again, while not strictly necessary it is a good idea to delete all system, but not data partitions. Disconnecting other drives is also highly recommended. These things simplify the installation and avoid unpleasant surprises if things proceed different than anticipated.

And always do a backup of your data before proceeding. Never rely on some Windows feature to do this for you. Many people have made some mistake and end up formatting and installing the OS on the wrong partition or drive. Even experts make mistakes. But experienced computer users anticipate that problems may occur and prepare accordingly (with backups).
My System SpecsSystem Spec
15 Nov 2016   #6

Windows 7 Pro x64 Windows 10 Pro x64

There is no reason to delete the install partition.

If someone were to delete the install partition and they did not want a system reserved partition, then the installer would create it.

It would be nice if the OP could post a shot of Disk Management before he reinstalls windows.
My System SpecsSystem Spec
26 Nov 2016   #7

Win 7 Pro x86

We never bother. Just put the image over the top or if disk install, custom allow this option so its all im one job format / install in steps of cause

really if you can only have the target HDD connected and clean all is best if possible

format should be enough thou
My System SpecsSystem Spec
26 Nov 2016   #8

Windows 7 x64

What is the purpose of wanting to re-install your Windows 7 system.

Do take note that is to install using OEM Recovery disk, there is this 1st partition for Boot, which is hidden.

That is why in post #2 @ThrashZone recommended should be done.

If you find that your system is slow, then do "disk defragmenter" the C:\ drive.
But do go to C:\Windows\Temp to delete all these useless files, just skip the files that cannot be deleted.
Also, go to C:\Users\Eric\AppData\Local\Temp <replace Eric to your User name> and deleted as mentioned above.
Finally then run the Disk Defragmenter.

Any re-install will required you to re-install other program, application, etc

Finally, you have to do Windows updates which may take a long time and sometimes it is very slow like not working, But it is work in-progress.
For short-cut on this do refer to post #2 @ThrashZone to show you how.

Your decision, as these replies are of several options for you to decide.
My System SpecsSystem Spec

 Should I reformat Windows partition before re-installing?

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