Kindle Fire Tip-Solving issue of "can't open file"

Have you ever encountered such an error message when trying to open your own .mobi, epub, or other documents on your Kindle Fire through the free your_kindle_account_name @ free.kindle.com?

"can't open file"

Possible solution (this may not work for you):

1. Go to Amazon App market to get the FREE app called File Expert. 
2. Install on your Kindle Fire.
3. Run File Expert
4. My Files ==> SD Card ==> Download ==> Select the file you just downloaded
5. A window pops out  " Open As...  ==> More... ==> Select "Amazon Kindle " app to open the file.
6. Done

Or you may try to move the files from the download folder into the documents one and reboot, see if you can read it directly.