There were numerous updates, here are only the more important things.
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Version 2.17
- Multipage-TIFF support ! (One of the first viewers with multipage TIFF support)
- Support for 'Exif'-JPEGs
- New option in "Properties->Copy/Move/Save": default 'save as' directory
- Rename-question for files with incorrect extension
- The Multiple-GIF timer is now much better  :)
- Some minor bugs fixed (very large GIFs, 'paste->save as')
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Version 2.15
- Multiple (animated) GIF Support ! IrfanView is the first graphic viewer 
  WORLDWIDE with Multiple GIF support. (One known bug: with some specially 
  transparency combinations)
  Much fun :) 
- New menu: Convert to 256 colors (for true color images only)
- Some WMF bugs are fixed (with old (Win 3.x) WMFs)
- Now: "Save as" with lower case names
- And you can copy my E-Mail address from "About-Box" :)
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Version 2.12
- The GIF-Decompression is now totally rewritten ! I hope without bugs :)
- Windows metafiles support (WMF=Windows Metafile and EMF=Enhanced Metafile)
- Command line support for AVIs (Fullscreen for AVI is not available)
- Some minor bugs fixed (startbar, extensions etc.)
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Version 2.10
- Print support
- "Always fit to desktop" was changed to "Always fit to desktop for big images"
- Some minor bugs fixed (GIFs, rotate under WinNT, overlapping)
- NEW ! Command line options: /one, /fs, /bf, /pos=(x,y), /title=text :
  /one        - force "only one instance"
  /fs         - force Full Screen
  /bf         - force Best Fit
  /title=text - set window title
  /pos=(x,y)  - move the window to x,y
Notes:
- Only lower case options are supported:
Examples: 
   i_view32 test.bmp /BF                 = incorrect
   i_view32 test.bmp /bf /title=My PIC   = correct
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Version 2.07
- AVI support (video for windows)
- Jump to first/last file in the directory (CTRL+F,CTRL+L)
- New option: always fit to desktop (properties->other options)
- Finally: "Save as", non-extension support
- Read support for extensions: *.jpeg, *.tiff
- Correct displaying of all Photo-CD files (rotate)
- Copy/move/delete windows
- Copying/moving: Replace question if the file exists (replace of read-only files)
- More hotkeys (rotate, flip, properties, image info etc.)
- Some minor bugs fixed (GIF,RAS)
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Version 2.05
- Edit options (Copy/Paste/Delete/Clear Clipboard)
- New in "Properties->Other options": allow Only 1 instance of IrfanView32
- Read-Header function is implemented, warning if incorrect extension
- Some fast-directory-view bugs fixed (like: last image)
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Version 2.00 
- Progressive JPEG support (read/save) 
- Alphabetical sorting of images in directory 
- Some minor bugs fixed 
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Version 1.99 
- New fast directory view ! This part is now totally rewritten; 
  no more lost files and uncomplete lists. Files are shown in the 
  order how they stay in FAT, that means unsorted. Coming in next release: 
  sorting files in alphabetical order. 
- Fixed bugs with some ICOs, and compressed BMPs 
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Version 1.98a
- Fixed bug with 256-colour-ICO
- Fixed bugs with fit-to-desktop and resize
- New menu outfit
- Zoom percentage shown in title bar
- Positioning window somewhere else than top left corner (biggest known bug: 
  IrfanView still can NOT correctly resize images whose dimensions exceed actual 
  screen resolution; if you do not want to cut edges of your image, void saving 
  in this situation)
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Version 1.98
- Viewing ICO 
- Zooming in and out 
   in: 150, 200, 250, 300, 400, 500, 600, 700, 800, 900 %
   out: 90, 80, 70, 60, 50, 40, 30, 20, 10, 5 %
   (known bug: zooming in large images works till now only up to 500 %)
- Resize image
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Version 1.97
- Viewing RAS
- Fixed some bugs with fast directory view and GIF
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Version 1.95
- Viewing TGA
- Image flip/rotate
- Image copy/move to another directory
- New tab-dialogs (Menu: Options->Properties)
- IrfanView32 doesn't support Win32s any more
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Version 1.90
- Viewing Photo CD
- "Fast directory view" (jump to next image in the current directory with space,
   to previous with backspace)
- Set image as wallpaper
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Version 1.85
- Windows 95-dialogs (open/save file)
- Viewing 2 bits per pixel PNG
- Saving file as TIFF
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Version 1.80
- Viewing PCX and RLE
- Viewing grayscale TIFF
- Fixed some bugs with GIF
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Version 1.70
- Viewing TIFFs (uncompressed, LZW, packbits, Huffmann
  fax group 3, fax group 4)
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