One of my pet peeves is getting a document to put on our school's website only to find it has been created in Microsoft Publisher. Unfortunately, Publisher files do not work well with other Microsoft Office applications such as Word. In other words, you cannot open a Publisher file using Word. Therefore if someone is trying to open a Publisher document Windows will look for a program to open the file unless you have Publisher, which many people don't.
The best way to upload any document is to convert the file into a PDF file first. There are two reasons for this. First, the Adobe Acrobat Reader is a free download and most computers have the program. Second, PDF files are smaller which saves space on websites. I have found an online PDF file converter by Neevia. All you do is go to the website, convert.neevia.com, click the browse button to select the file you wish to convert, then click convert. Once the conversion process is complete you can open the PDF file and save it. The website is free but there is a 1MB size limit on the file you wish to convert.