.Net Framework 3.5 installation fails on Windows Server 2016
Tried many solutions like below
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Grant read permission to the Everyone group on the installation files. Check: https://docs.microsoft.com/en-us/windows-server/administration/server-manager/install-or-uninstall-roles-role-services-or-features
Important When you are installing feature files from a remote source, the source path or file share must grant Read permissions either to the Everyone group (not recommended for security reasons), or to the computer (local system) account of the destination server; granting user account access is not sufficient. Servers that are in workgroups cannot access external file shares, even if the computer account for the workgroup server has Read permissions on the external share. Alternate source locations that work for workgroup servers include installation media, Windows Update, and VHD or WIM files that are stored on the local workgroup server.
Important
When you are installing feature files from a remote source, the source path or file share must grant Read permissions either to the Everyone group (not recommended for security reasons), or to the computer (local system) account of the destination server; granting user account access is not sufficient.
Servers that are in workgroups cannot access external file shares, even if the computer account for the workgroup server has Read permissions on the external share. Alternate source locations that work for workgroup servers include installation media, Windows Update, and VHD or WIM files that are stored on the local workgroup server.