The Win32 and Win64 versions of USEARCH require a Windows dynamic link library (DLL) named vcomp100.dll. This is a mistake on my part -- I make a lot of effort to ensure that USEARCH has no dependencies on external files because this is inconvenient for the user and can lead to subtle compatibility problems and crashes. Unfortunately, I overlooked this dependency, and there appears to be no practical way to remove it.

The simplest fix is to download the DLL from the link below and copy it into your Windows\System32 folder. If that doesn't work for some reason, you could try using one of the official installers from Microsoft (see links below). These install several other DLLs that you don't need, so I recommend trying the simple fix first.

Download vcomp100.dll from drive5.com. Right-click on the link and use Save As... to copy it to your System32 folder.

32-bit installer

64-bit installer