DOS DEL command data loss hit construction site after manager tried PC

A DOS DEL command data loss incident from the 1980s is the latest cautionary tale in The Register's “Who, Me?” column: a junior manager on a Swedish construction site reportedly deleted files from an engineer's PC after trying the only command he knew. The financial impact, recovery process and exact data affected were not disclosed, which leaves this as an anecdote rather than a fully documented postmortem.

The Register said the reader, anonymized as Clay, was the most junior member of the management team at the construction site. At the time, PCs were not yet common across the workplace, and only two site engineers had computers, according to the account.

Clay told The Register he was curious about the machines and asked the junior engineer during a lunch break whether he could try using one. The engineer allowed him access, and Clay entered the command he knew: “DEL *.*”.

That was enough to remove the files in the directory available to him, according to Clay's account. The Register reported that the engineer took the incident calmly and that Clay kept his job. Clay also told the publication that the command still stays with him decades later.

What does DEL *.* do in DOS?

In DOS, DEL is the delete command, and *.* is a wildcard pattern that matches file names with any name and extension in the current directory. Used in the wrong place, it can erase a working directory's contents without the guardrails modern users expect from graphical operating systems.

The story is old, but the operational lesson is not. Access control, backups and user permissions exist because curiosity and confidence are poor substitutes for training, especially when a command line gives a user direct access to production or business-critical files.

The Register did not say whether the deleted material was restored from backup, recreated manually or lost permanently. It also did not identify the company, the construction project or the specific PC setup involved. Those omissions limit what can be concluded about the severity of the incident.

For technology teams, the useful part is the failure mode: a non-technical manager was given hands-on access to a machine used by an engineer, with no mention of sandboxing or restricted permissions. That pattern still appears in modern forms, from shared admin accounts to cloud consoles opened for a quick demo.

The incident also shows why old tools remain relevant in security and operations training. The command itself belongs to a different computing era, but the risk is familiar: a user with enough access can turn a small experiment into data loss in seconds.

This story draws on original reporting from theregister.