If i have .NET framework 4.0 installed, but programs running with framework 3.5 refuse to run on my machine, can i just install framework 3.5, and the programs start running (with framework 4.0 still installed and programs running with framework 4.0 can still run)? or will framework 4.0 become useless with the installation of framework 3.5

Vista and .net Framework - social.msdn.microsoft.com Also, just because you have folders named v1.0.3705 and v1.1.4322 does not mean that you have the .NET Framework 1.0 or 1.1 installed. The .NET Framework 2.0 installs a few files to each of those folders for backwards compatibility reasons. Thanks! Aaron Repair .NET Framework on Vista? | Vista Forums Dec 26, 2007

.NET Framework 1.1 may also be automatically removed and uninstalled if you upgraded to newer Windows operating system from Windows 7 or Windows Vista. However, the slipstream .NET Framework 1.1 with SP1 integrated may be able to be used to install .NET Framework 1.1 on to Windows 8, Windows 8.1, Windows 10 and their server equivalents.

VistaDB is a fully compliant ADO.NET data provider with support for Entity Framework, ADO.NET, and Typed Datasets as well as its own Direct Data Access API for efficient cursor-based operations. Thanks to ADO.NET, VistaDB is already compatible with a wide range of …

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Determine which .NET Framework versions are installed The .NET Framework consists of two main components, which are versioned separately: A set of assemblies, which are collections of types and resources that provide the functionality for your apps. The .NET Framework and assemblies share the same version number. For example, .NET Framework versions include 4.5, 4.6.1, and 4.7.2. Download .NET Framework 4.8 | Free official downloads