Some possible reasons:
Job descriptions are in PDF format. Macs use Preview to read PDFs. Firefox will try and default to an Adobe reader. This might cause problems. You can change the settings of your browser to use one or the other. Occasionally updates to the operation system or browser might reset or 'break' this behavior again. It is a known issue that Mac OS X does not work well with Gecko based browsers. Here are a couple of add-ons that may also be useful:
Newer PDF's use security features that may not run in older browsers and/or conflict with security settings, here are 2 possible solutions:
To read about the solutions in greater detail: http://www.bnl.gov/itd/webapps/pdf_help.asp
There is no need to keep applying for the same position. One time puts you directly into our database. If you are a fit, we will contact you. You are welcome to apply to other positions.
Use the Referral field only if someone is actually referring you to us.
We test this website in Windows, Mac and Linux and across multiple browsers. But, the older your browser, the greater chance something may not work as expected. Please use the Contact Webmaster link if you find a bug. It is still very important to us. An update to an operation system, a patch to a browser, etc. could cause things to 'break' and reporting this directly helps us stay on top of these issues.