Interesting Mac support call today. Kevin was using Appleworks under OS 9 on an iBook to write documents. He then wanted to open them in Appleworks under OS X on his iMac. Transfer was easily achieved and then they wouldn’t open. Double-clicking brought up the Choose Application dialog. We chose AW and it wouldn’t open. We tried Open from within Appleworks. No go. We tried Get Info and Always open with AW. No go.
Finally I realised he didn’t have .cwk at the end of the filename. Curious, as later versions of AW always offer to add it. His version didn’t and so he hadn’t used it. Added the extension and all was sweet under OS X. Problem solved. 30 minutes.