Microsoft WinHelp is a proprietary format for online help files that can be displayed by the Microsoft Help browser winhelp.exe or winhlp32.exe. The file format is based on Rich Text Format (RTF). It remained a popular Help platform from Windows 3.0 through Windows XP. WinHelp was removed in Windows Vista purportedly to discourage software developers from using the obsolete format and encourage use of newer help formats. History 1990 – WinHelp 1.0 shipped with Windows 3.0. 1995 – WinHelp 4.0 shipped with Windows 95 / Windows NT. 2006 – Microsoft announced its intentions to phase out WinHelp as a supported platform. WinHelp is not part of Windows Vista out of the box. WinHelp files come in 16 bit and 32 bit types. Vista treats these files types differently. When starting an application that uses the 32 bit .hlp format, Windows warns that the format is no longer supported. A downloadable viewer for 32 bit .hlp files is available from the Microsoft Download Center. The 16 bit WinHelp files continue to display in Windows Vista (32 bit only) without the viewer download. January 9, 2009 – Microsoft announced the availability of Windows Help program (WinHlp32.exe) for Windows Server 2008 at the Microsoft Download Center. October 14, 2009 – Microsoft announced the availability of Windows Help program (WinHlp32.exe) for Windows 7 and Windows Server 2008 R2 at the Microsoft Download Center. October 26, 2012 – Microsoft announced the availability of Windows Help program (WinHlp32.exe) for Windows 8 at the Microsoft Download Center. November 5, 2013 – Microsoft announced the availability of Windows Help program (WinHlp32.exe) for Windows 8.1 at the Microsoft Download Center. July 15, 2015 - Microsoft completely removed Windows Help from Windows 10. Attempting to open a .hlp file just brings users to a help page detailing that it was removed. File format A WinHelp file has a ".hlp" suffix. It can be accompanied by an optional table of contents (.cnt) file if the help developer created one. When Windows opens a WinHelp file, it creates a .gid file in the same directory or in "%LOCALAPPDATA%\Help", containing information about the .hlp file such as the window size and location. If the user clicks the "Find" tab and enables keyword indexing, Windows creates an index file with a .fts (full text search) extension. Annotations and bookmarks for each Windows help file have the extension ".ann" and ".bmk". A number of software