Windows System Errors

Windows System Errors 20 — ERROR_BAD_UNIT

In Windows System Errors, code 20 is ERROR_BAD_UNIT. The official source describes it as “The system cannot find the device specified.”. Its concrete cause depends on the operation and surrounding message.

Code20
SymbolERROR_BAD_UNIT
Source confidencehigh

Official definition

The system cannot find the device specified.

In plain language

In Windows System Errors, code 20 is ERROR_BAD_UNIT. The official source describes it as “The system cannot find the device specified.”. Its concrete cause depends on the operation and surrounding message.

Context to inspect

  • The surrounding operation, version and subsystem determine the actual cause.
  • The same numeric value can mean something different in another namespace.

Safe first checks

  1. Confirm which product, protocol or subsystem produced the code.
  2. Read the full surrounding error message and inspect relevant logs.
  3. Compare the code with the linked authoritative documentation before changing configuration.

Important context

The surrounding operation, version and subsystem determine the actual cause.

Authoritative source

Microsoft Learn — System Error Codes

Related codes