TOS Error -36
Atari Atari ST
Severity: MinorWhat it means
TOS Error -36 (EDSKFULL) means the disk is full — there is no space left to save the file.
Delete unneeded files or use a different disk.
Affected Models
- Atari ST
- Atari STe
- Atari Mega ST
- Atari TT030
- Atari Falcon
Common Causes
- Floppy disk is full (720K or 880K capacity exhausted)
- Hard disk partition is full
- Trying to save a file too large for the remaining space
How to Fix It
-
Check the free space on the disk.
Click on the disk icon and choose Show Info (or equivalent in your GEM desktop version).
This shows used and free bytes. -
Delete files you no longer need.
Move important files to another disk first, then delete what you can.
-
Use a new blank floppy if the current one is full.
Standard ST floppies hold 720K (SS) or 720K/880K depending on format.
High-density drives can format 1.44MB floppies. -
On hard disk: archive old projects to floppy to free space.
ST hard drives were typically 20–80MB — small by modern standards.
Regular archiving was part of the workflow.
Frequently Asked Questions
What is the maximum floppy capacity on an Atari ST?
Standard DD (double-density) floppies hold 720K in the default TOS format.
With third-party tools and a modified drive, 880K was possible.
HD floppies (1.44MB) required a high-density drive not standard on the original ST.