Need help with Kindle book transfer [View all]

I have an old Lenovo Android tablet that has been my e reader for about a year now. Suddenly it will not connect to the WiFi on my modem. (That is a whole other problem that will be discussed tomorrow with my internet provider.)

I figured that I can probably sync the books I have paid for from Amazon with Kindle on my computer (where I have not had Kindle, but will install it in a few minutes, after it finishes downloading). Amazon only talks about transferring Kindle files to their devices - is it as easy as that with non-Amazon devices? All they say to do is to hook up the Kindle device via USB, and transfer the files into the correct folder on the tablet or whatever.

I've tried that, put the files into the folder on the Andriod tablet where the other book files were, but the ones that had not been previously downloaded on the Android tablet do not show in the Kindle library.

If I can't figure out how to do this or how to get the tablet to connect to the WiFi, it may be the end for my tablet.