Latest release of ProDOS is 2.4.3

ProDOS 2.5 alpha 8 pre-release is available

ProDOS 2.4.3

Download ProDOS 2.4.3

Announcing ProDOS 2.4.3 for all Apple II computers


Bugs fixed:

  • Fix long standing bug where CATALOG would fail on directories that have 128 blocks or more.
  • Fix crash starting A2osX (issue 55).
  • Fix bug where ProDOS would not distinguish disks with the same volume name, (issues 46) and (issue 50).
  • Fix splash screen to not use lower case on II and II+ machines with a 65C02 or 65816 CPU upgrade.
  • Fix long standing bug that prevented creating more than 33024 files in a directory.
  • Fix long standing bug where SET_MARK on directories would fail for offsets past block 128.



  • ADT Pro removed from the disk image because of size constraints

  • Thunderclock driver updated for years 2023-2028, (issue 72).

BASIC.SYSTEM changed from 1.6 to 1.7:

  • Delete key is mapped to left arrow.
  • RENAME command supports using space (new) or comma (as before) between the filenames, e.g. RENAME f1 f2.
  • Bump IVERSION to 7 at globals $BFFD


Please file bug reports at:




— John Brooks and Friends


Twitter: @JBrooksBSI


Download ProDOS 2.4.3


If you’d like to support John Brook's efforts to improve the Apple II, donations are welcome using: PayPal