Part 3: Immediate Symptoms (How to Confirm the Problem)
You do not need to be a detective. The error presents itself clearly:
Texture Fill Preview is black or white. Open the Texture Fill dialog (shortcut: F11 > Texture fill). Instead of a preview thumbnail, you see a blank square.
Library dropdown is empty. The "Texture library" dropdown (e.g., "Samples," "Standard") shows no options or only "User defined."
Error on every texture selection. Click any texture style (e.g., "Canvas," "Rough"), and the message pops up.
Corrupted file on open. You open an old .CDR file that contains a texture fill, and the object turns solid black or white.