What will happen to a document that was check-out from a document library in SharePoint 2007 when the client computer crash? (e.g. Is the check-out forever lost? Is there a need to check-out the document again?)
If the client computer crashes that will not cause a problem. When someone checks out a document that just means it is marked as Checked Out by that user. The document can be checked back in by that user from another client computer.