From PSB thread
about 4 weeks in the cupboard, freezing is months and about 8 weeks in the fridge.
from here ...
http://www.route66beefjerky.com/faq.html
What is the shelf life of your beef jerky?:
Answer: Because most of the moisture is removed through drying, it is shelf life stable and can be store without refrigeration, making it a handy food for backpackers and others who don't have access to refrigerators. Commercially packaged jerky can be kept 12 months - home dried jerky can be stored 1 to 2 months.
taken from here ...
http://www.askthemeatman.com/faq.htm
There are a couple of possibilities. Also, not all jerky will mold, it depends on a few things. The number 1 reason jerky will mold is that not enough moisture has been removed from the meat during the drying process. Jerky should have around 90 to 95% of the moisture in the meat removed during drying. If it doesn't, the moisture still in the meat leads to the possibility of mold spores growing. If the jerky is dried almost completely, mold usually won't grow. If you like your jerky a little moist, you could try to vacuum pack your jerky. Mold will not grow without air ( or oxygen ). There are some decent home vacuum packers on the market now, and these might be of use. Also, mold seems to grow or develop quicker in a moist atmosphere. So, the refrigerator is not a good place to store jerky, unless it is vacuum packed. But since jerky is dried meat, it is not necessary to store it refrigerated anyway.