Two possible solutions.
One: the problem computer isn't calling (vl-load-com) when drawings are opening. This may be an oversight, or a global LISP file isn't being loaded due to the security settings.
Two: something has been installed or uninstalled incorrectly. I've seen this happen when installing a BETA release new version alongside an older version. If a call to (vl-load-com) doesn't fix anything, and case Two is correct, you'll need to do a full uninstall/re-install (repair and reset doesn't cut it).