A WebmasterWorld thread has a documented case of one webmaster forgetting to renew his domain name after a day or so. Then after the domain name expired, he renewed the domain and got things back up after maybe two days.

The issue was, he also noticed that his domain name was no longer showing up in the Google search results. He said:

WebmasterWorld administrator, Tedster, told the webmaster that in many cases your domain will be lost in Google until you renew it. It might take a few days for the domain to reappear in Google. Tedster was right, a few days later, the webmaster came back in to let us know his site was indexed and ranking again.

Please don’t forget to renew your domain name. The couple day loss in traffic might not be the end of the world, but leaving your domain name open for others to grab and use, can be extremely painful.

Forum discussion at WebmasterWorld.