- last updated Feb 13, 2017 -SETUP .NET Framework 1.1/2.0/3.0/3.5/4.0/4.6+ on Windows XP/2003 and newer: * ALWAYS REBOOT WHEN PROMPTED, and DISABLE ANTIVIRUS before each install. * * Shut down any background applications before each install. * * Windows Vista & Server 2008 have .NET 3.0 (includes 2.0) pre-installed. * Windows 7 & Server 2008 R2 have .NET 3.5 ( includes 2.0/3.0) pre-installed. * Windows 8 & Server 2012 have .NET 4.5 (includes 4.0) pre-installed, and 3.5 (includes 2.0/3.0) can be enabled in the Control Panel, by clicking "Turn Windows features on/off". * Though .NET 4.5 "replaces" 4.0, it does not include every feature, so this procedure will install 4.0 first 1) Install: dotnetfx.exe (.NET Framework 1.1) 2) Install: NDP1.1sp1-KB867460-X86.exe (Service Pack 1 for .NET 1.1) 3) Reboot, even if not prompted. 4) Install: NDP1.1sp1-KB2416447-X86.exe (Security update for .NET 1.1 SP1) 5) Reboot, even if not prompted. 6) Install: dotnetfx35.exe (.NET Framework 3.5 with SP1) OR: turn on ".NET 3.5.1" feature in the Control Panel (7/8/2008R2/2012) 7) Install: NDP20SP2-KB958481-x86.exe (for 32-bit XP/2003/Vista) OR: NDP20SP2-KB958481-x64.exe (for 64-bit XP/2003) OR: NDP35SP1-KB958484-x86.exe (for 32-bit Vista/2008) OR: NDP35SP1-KB958484-x64.exe (for 64-bit Vista/2008) 8) Install: NDP30SP2-KB958483-x86.exe (for 32-bit XP/2003) OR: NDP30SP2-KB958483-x64.exe (for 64-bit XP/2003) OR: Windows6.0-KB958481-x86.msu (for 32-bit Vista/2008) OR: Windows6.0-KB958481-x64.msu (for 64-bit Vista/2008) 9) Install: NDP35SP1-KB958484-x86.exe (for 32-bit XP/2003) OR: NDP35SP1-KB958484-x64.exe (for 64-bit XP/2003) OR: Windows6.0-KB958483-x86.msu (for 32-bit Vista/2008) OR: Windows6.0-KB958483-x64.msu (for 64-bit Vista/2008)10) Reboot, even if not prompted.11) Install: dotNetFx40_Full_x86_x64.exe (.NET Framework 4.0) 12) Install: NDP472-KB4054530-x86-x64-AllOS-ENU.exe (.NET Framework 4.7.2)13) Visit http://update.microsoft.com and install all .NET updates.14) Reboot, even if not prompted.15) Repeat steps 13&14 until no more .NET updates show up.IF A .NET FRAMEWORK UPDATE WON'T INSTALL: (typical fix time = 1-2 hours) Run (as admin) "chkdsk /f c:" and answer Yes, then reboot. Disable antivirus, backup software, and any background applications. Go into Control Panel > Add/Remove Programs, and TRY to remove all .NET Frameworks, starting with the highest version and working down. (At least one will probably fail to uninstall.) On Windows Vista/2008 and newer, go to the Control Panel, click "Turn Windows features on or off", and turn off all .NET Framework features. Run the dotnetfx cleanup tool, and remove ALL .NET versions. Reboot. Run (as admin) "net stop wuauserv" then QUICKLY do the next two steps. Rename or delete "C:\Windows\SoftwareDistribution". Delete the contents of "%TEMP%" and "C:\Windows\Temp". Finally, follow the .NET Framework setup instructions.