While the "Turn Windows Features on or off" GUI (accessed by typing optionalfeatures in the Start Menu) is the most user-friendly method, it forces the computer to check Windows Update by default.
If your computer lacks an active internet connection, or if you encounter the dreaded during standard installation, using an offline installer method is your best and most reliable solution. Why Do You Need an Offline Installer?
Ensure you are pointing to the sources\sxs folder specifically, not just the root of the drive. Net Framework 3.5 Offline Installer Windows 10 64 Bit
Type gpedit.msc in the Windows Run dialog to open the Local Group Policy Editor.
If your computer is offline or blocked by a firewall, this process fails instantly. To successfully install , you must use "Feature on Demand" methods that point the operating system to a local file source rather than the internet. While the "Turn Windows Features on or off"
DISM /Online /Enable-Feature /FeatureName:NetFx3 /All /LimitAccess /Source:X:\sources\sxs
The ability to install on Windows 10 64-bit is an essential skill for IT administrators, developers maintaining legacy code, and power users running classic games. The online installer is unreliable; the GUI feature is broken by design. But with a Windows 10 ISO and a single DISM command, you can install it in under five minutes—no internet required. Ensure you are pointing to the sources\sxs folder
You might ask: "My Windows 10 is 64-bit and fully updated. Why do I need a framework from 2007?"
Insert it into your computer and note the drive letter in File Explorer. 2. Open Command Prompt as Administrator Click the Start menu and type cmd . Right-click Command Prompt and select Run as Administrator . Click Yes on the User Account Control (UAC) prompt. 3. Execute the DISM Command Copy and paste the following command into the window:
/Source : Points to the specific folder containing the necessary files.