As a service provider, I never want to say, “Can you send that again? I don’t know how, or I can’t open that file type.”
Instead of asking for a different file type, I usually use one of the MANY online converters.
Convert Microsoft Publisher to a PDF
For instance, just today, I used a Pub to PDF (https://www.zamzar.com/convert/pub-to-pdf/) converter to view the details of a Publisher file a client emailed over. This client emailed me the Microsoft Publisher file rather than an image or a PDF file. I just needed to read the details of the files and capture the date, time, and cost, so using an online converter was the perfect tool for the job.
Now, as a caveat, if a client sends a low-res JPG and I need a vector file, I’ll ask them to keep digging until they find an editable file I can use and manipulate. However, if they send me a Publisher file and I don’t use Microsoft Publisher, I will not ask them to send it again.
New designer tip: use online converters
Essentially, if a client sends you a file, you can convert it to anything you need with online converters.
Use an online converter to turn this native Microsoft Publisher file ending in a .pub extension into a PDF. A good example is the Pub to PDF online converter.