Hi WSC33
Could you please share the following details so that we can help you better?
1. Os version you are using - Win7/Win8/Mac OS 10.9/Mac OS 10.8 ?
2. 32 bit or 64 bit OS ?
3. Firefox version you are using
Also could you please try to disable and then re-enable the Adobe Acrobat 10 ad-on from Firefox, restart Firefox and try to convert a webpage and let us know, if the issue is still reproducible?
Thanks
Tanvi