2651 Multimedia Viewer Book Aggregate Multimedia Viewer Book is a format developed by Microsoft and used by programs such as Encarta to provide interactive, browsable multimedia. The format is very similar to the Microsoft Help .hlp format fmt/474, and a decompiler for the file format, helpdeco is available under a GNU license: https://github.com/pmachapman/helpdeco. The .hlp format this is based on was deprecated with Windows Vista. 244 Preservica / Preservica 23 Nov 2022 23 Nov 2022 fmt/1800 PUID mvb File extension 2139 Multimedia Viewer Book BOF offset 0, 4 byte magic 0x3F5F0300, later SYSTEMHEADER 0x6C03, Format version WMVC/MMVC media view file: 0x1B00, Major version: 0x0100. Reference: http://delphi-kb.blogspot.com/2010/07/detailed-description-of-winhelp-file.html 1 Absolute from BOF 0 0 3F5F0300*6C031B000100