On one of our computers, some websites behaved very weird; pages could not be found and they were redirected to mybrowserbar.com. I found this on Wikipedia about PDFCreator:

Starting with version 0.9.7 (February 2009), PDFCreator has included a new toolbar application that is considered by many to be malicious software. The end-user-license agreement for Pdfforge Toolbar by Spigot, Inc. (versions prior to 0.9.7 have a different, optional toolbar called “PDFCreator Toolbar”), states that the software will: modify your Microsoft Internet Explorer and/or Mozilla Firefox browser settings for the default search engine, address bar search, “DNS error” page, “404 error” page, and new tab page to facilitate more informative responses as determined by The Toolbar.

The opt out procedure is difficult, but possible:

The opt-out procedure during installation is confusing. There are two separate screens where the user must take action if they do not wish to install the toolbar, one of which is not clearly labeled. This confusing process leads many users to believe they have opted-out of the installation when they have not. Some users erroneously report that it is not possible to opt-out of the toolbar installation, which is not true. If one reads the instructions carefully and follows them, it IS possible to install PDFCreator without also installing the unwanted toolbar, even if the process is confusing.

I may want to consider another PDF printer.