We have found 3 software records in our database eligible for .pub to .docx file format conversion.
With Microsoft Publisher, users can export their own document files (.pub) to any of the available MS Word formats (.doc, .docx). Just open up the file Publisher and use the File ► Save as.. menu to save your document as .docx.
If you do not have access to Publisher, you will have to rely on some of the 3rd party solutions like OpenOffice or similar. However, it is always best to use the original software because of compatibility reasons and using 3rd party all for pub to docx conversion may result of some data being lost.
PUB
Files with pub extension are in most cases documents created in Microsoft Publisher, a desktop publishing application from Microsoft Office suite. PUB documents are much more complex than common Word files and give more emphasis to design and page layout, rather than actual text.
DOCX
Files with docx extension are documents written and saved using Microsoft Word word processor edition 2007 or later. DOCX format replaced the previously used DOC format, moving from binary files to Open XML schema-based documents. They are supported in almost every modern word-processing tools.