Article Title: RiverTools 4.0 runs on Windows 8.0 but not Windows 8.1
Article Name: WINDOWS2
OS Platforms: Windows 8.1
Last Updated: 10/15/2015


This Tech Tip explains how to solve a problem where RiverTools 4.0 runs under Windows 8.0 but not under Windows 8.1.


After a fresh install of Windows 8.1, or an update from Windows 8.0 to 8.1, the InstallAnywhere installer for RiverTools 4.0 may not complete the installation, or RiverTools 4.0 may fail to start up after the installation is complete.

There are several DLL files (Dynamic Link Library) that are included with a Windows 8 installation in the folder: C:\Windows\System32 that are not included with a Windows 8.1 installation. RiverTools 4.0 — and many other programs out there — require these DLLs, which are part of the Microsoft Visual C++ distribution. The 3 specific DLLs that RiverTools 4.0 needs are:

  • mfc100u.dll
  • msvcp100.dll
  • msvcr100.dll
Note that 2 of these start with MSVC for MicroSoft Visual C++. The best (and most secure) way to get these missing DLLs is to download and run an executable that Microsoft has provided to solve this problem. The 64-bit version of this Microsoft executable is available at:

        Microsoft Visual C++ 2010 Redistributable Package (x64).

It is a very quick install that copies some DLLs (including the 3 mentioned above) into C:\Windows\System32. The 32-bit version of this executable is available at:

        Microsoft Visual C++ 2010 Redistributable Package (x86).

Before downloading and running the appropriate patch from Microsoft, it is a good idea to run Windows Update and make sure that all recommended updates have been installed.

By the way, the files in the Windows\System32 folder are to support 64-bit applications, and the files in the Windows\SysWOW64 folder are to support older 32-bit applications, opposite of what most people would think. You can learn more about these two folders at:

        The 'Program Files (x86)' and 'SysWOW64' folders explained.

If you have any additional questions or comments, please contact Rivix Technical Support for assistance.

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