RAR files are compressed versions of usable computer files, similar to Zip files. The RAR format is often used to shrink a large file, making it easier to upload to the Internet or to an e-mail message. If you have a PDF file compressed into an RAR file format, the only way to access the PDF information is to convert the RAR file back to the original PDF.
Locate the RAR file you want to extract.
If you do not have an RAR extraction program you must download and install a program to extract RAR files, such as WinZip, WinRAR or RAR Extract Frog (see the links in the Resource section). All programs function the same, however, WinZip is only a trial program (it lasts for 30 days before requiring you to purchase it).
Right-click the RAR file and select "Extract." A small program window appears with the RAR file listed in the middle.
Choose an extraction location. This is where the PDF file is placed once it's converted from the RAR format.
Click "Extract" and the RAR file is converted back to the PDF. You are now free to use the PDF file.