Check to see if there is a number you can call or fax or snail mail them. They must have thought that no one cancel.
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"How do I cancel my Tripod Paid subscription?
To cancel a Tripod Paid Account (Tripod Plus, Tripod Pro, Tripod Webmaster, Tripod Deluxe):
If you have a Tripod Paid account (Tripod Plus, Tripod Pro, Tripod Webmaster, Tripod Deluxe) and you would like to keep your Web site up but downgrade back to the Free service, you may do so at any time. Keep in mind that if you are cancelling a Pro, Webmaster or Deluxe plan, you will lose your domain name if you downgrade to Plus or Free or if you cancel altogether.
Please log into Tripod and then go to the My Account page. At the bottom there will be a link that says Cancel your Membership under the Membership Information area. Click on this link and click on the YES, I want to CANCEL button. Make sure you fill out all the required fields on the Cancellation Survey page. You will be prompted to enter your password again. Then verify your membership information by clicking "I Agree" at the bottom of the page.
Sometimes this process will go slowly as it is being processed. If you close your browser, hit stop, or hit the back button, the cancellation will not go through and you will still be charged as a paid user. If you arent sure if the cancellation went through, log out, then log back in to your My account page to check on your account status.
Once that has been processed, your auto renew will be turned off and your Web site will revert to the Free service.
To delete your web site, please log into Tripod and go to the My Account Page. At the bottom there is a link that says .Cancel your Membership. Click on that and you will be prompted to type in your password again. If you are sure you need to delete your web site, click on the Delete Everything button.
No sure if this helps.