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Preparing for Installation
You can upgrade to the latest version of Fedora manually instead of relying on [application]*dnf system upgrade*. This involves booting the installer as if you were performing a clean installation, letting it detect your existing Fedora system, and overwriting the root partition while preserving data on other partitions and volumes. The same process can also be used to reinstall the system, if you need to. For detailed information, see xref:../advanced/Upgrading_Your_Current_System.adoc#sect-upgrading-fedora-manual-reinstall[Manual System Upgrade or Reinstallation].
Downloading Boot and Installation Images
The Fedora Project offers different Editions tailored for some specific use cases. Choose the Fedora Edition best for you, or you can build your own by customizing after the installation, or by using a kickstart file as described in xref:../advanced/Kickstart_Installations.adoc#sect-kickstart-file-create[Creating a Kickstart File]. Kickstart installation requires the `netinstall` media type, or a direct installation booting method such as PXE; kickstarts are not supported with live images.
Read more about Fedora Workstation, Fedora Cloud, Fedora Server and the available media types in xref:../Downloading_Fedora.adoc#chap-downloading-fedora[Downloading Fedora].
You can also choose a Fedora _Spin_ featuring favorite alternative desktops or tools for specialized tasks at link:++http://spins.fedoraproject.org++[].
Verifying the Downloaded Image
Because transmission errors or other problems may corrupt the Fedora image you have downloaded, it is important to verify the file's integrity. After the images are created, an operation is performed on the file that produces a value called a `checksum` using a complex mathematical algorithm. The operation is sufficiently complex that *any change* to the original file will produce a different checksum.
By calculating the image's `checksum` on your own computer and comparing it to the original `checksum`, you can verify the image has not been tampered with or corrupted. The original checksum values are provided at link:++https://fedoraproject.org/verify++[], and are [command]#gpg# signed to demonstrate their integrity.
Verifying checksums on Windows systems
Download the Fedora image of your choice from link:++https://fedoraproject.org/get-fedora++[] and the corresponding checksum file from link:++https://fedoraproject.org/verify++[]
Open a [command]#powershell# session.
Change to the directory containing the downloaded files.
> cd $HOME\Downloads\
> ls
Directory: C:\Users\Pete\Downloads
Mode LastWriteTime Length Name
---- ------------- ------ ----
-a--- 11/25/2014 12:39 PM 272 Fedora-Server-21-x86_64-CHECKSUM
-a--- 11/25/2014 12:39 PM 2047868928 Fedora-Server-DVD-x86_64-21.iso
Load the resources required to calculate the checksum.
> $image = "Fedora-Server-DVD-x86_64-21.iso"
> $checksum_file = "Fedora-Server-21-x86_64-CHECKSUM"
> $sha256 = New-Object -TypeName System.Security.Cryptography.sha256CryptoServiceProvider
> $expected_checksum = ((Get-Content $checksum_file | Select-String -Pattern $image) -split " ")[0].ToLower()
Calculate the downloaded image's checksum. This will take a while!
> $download_checksum = [System.BitConverter]::ToString($sha256.ComputeHash([System.IO.File]::ReadAllBytes("$PWD\$image"))).ToLower() -replace '-', ''