For example, the solution to severalDevice Manager error codesincludes removing specificregistry valuesfromregistry keysnamed after a gadget’s GUID.

This is not an exhaustive list, and not all Windows versions use every GUID in this table.

Several less common system-defined unit classes exist.

Close up picture of an open hard drive

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Also, devices can generate unique classes based on variables, which makes it impossible to list them all.

What Are GUIDs?

Windows creates the GUID, written inhexas a 128-bit alphanumeric string, for each piece of hardware.