Export to PDF
The final format for your poster file must be the Adobe Acrobat PDF file type. These files have the extension .pdf. This "portable document format" will contain all of the fonts that your poster needs within the file, unlike PowerPoint or Illustrator. This file format will ensure that your poster will have the fewest possible typesetting, layout or overall design issues.
In order to export your poster file from Microsoft PowerPoint, go to File then Save As, and in the Save As window, under Save as type: make sure you choose Adobe PDF.
Similarly, to export your poster file from Adobe Illustrator, click File then select Save As.... and from the list of available types, select Adobe PDF (*.PDF).
Once you've saved your poster file to the PDF format, you should verify that the poster dimensions are correct. In Adobe Acrobat, open your poster file and go to File then Properites and in the Document Properites window, click on the Description tab. Near the bottom of the window, under Page Size:, you will see the poster dimensions of your PDF file.
These dimensions must match your requested poster dimensions.