FileInfo.com - The File Extensions Resource

.WP5 File Extension

File Type	WordPerfect 5 Document
File Format	File
Common?	No
File Description	Word processing document created by WordPerfect 5.x for DOS, a highly successful version of WordPerfect; included support for tables within the document.
Program(s) that open wp5 files	Windows: Corel WordPerfect 5 or later

Information from FileInfo.com - The File Extensions Resource.
http://www.fileinfo.com/extension/wp5