Windows does not natively support CorelDRAW (.CDR) thumbnails. The shell extension adds a thumbnail handler that renders previews directly in File Explorer, saving you from opening dozens of files to find the right one.
To download and install the Corel Graphics Windows Shell Extension, follow these steps: corel graphics windows shell extension download
"Come on," Elias muttered, taking a swig of lukewarm coffee. He clicked a file. Open with... Choose another app. Windows does not natively support CorelDRAW (