One of the coolest things about the Kindle is that it keeps your content in sync via the Amazon Whispersync service. So you can skip between your kindle, the iPhone app or even the Cloud Reader in your web browser and stay on the same page in your reading material. Amazon takes care of all of this in the background for you. The problem is, if you for some reason decide to skip way ahead on one of your devices or, if you liked your book and want to read it again in the furture, Whispersync thinks you are done and continues to ask if you want to sync to that furthest location. The awesome Whispersync becomes more of a nusance at this point.
There isn’t a quick method that I have found to be able to reset your furthest point read. What I am about to detail is not hard but you have to go methodically through the steps and don’t skip any. You may want to print this page.
1. Grab one of your devices and try syncing your book. Make sure you get a message that you are at the furthest location. If you are not, then go ahead and sync to that location.
2. Close out of your book.
3. Open the book again and try syncing. You should get a message that you are at the furthest location across all devices.
4. Set your device down and on your computer
5. Visit the Manage Your Kindle page http://www.amazon.com/manageyourkindle.
6. Click Manage Your Devices under Your Kindle Account on the left side of the page.
7. Under Whispersync Device Syncronization at the bottom of the page, click “Turn Off.”
8. Stay on this page on your computer and pick up your device again
9. Got to the beginning of your book and try syncing.
10. If you do NOT get a message that you are at the furthest location, click No.
11. Close your book
12. Click sync to refresh your library
13. Open your book and be sure you are at the beginning then try syncing again. If you do NOT get a message that you are at the furthest location, click No and go back to step 12.
14. Close your book
15. Set you device down and, again at your computer, click “Turn On” on the Whispersync Device Syncronization page.
16. Pick up your device again and, to be safe, sync your library again
17. Open your book and try syncing it again. It should now be at the furthest location and you are done.
18. If you have another device, pick that up now.
19. Sync to refresh your library
20. Open your book and go immediately to the beginning
21. Sync your book and you should now be at the furthest page read across all your devices.
If you have more devices, go back to step 18.
Hopefully that worked for you. It has worked for me for several books.