Do not use 7-zip to extract our RAR archives because it becomes out-of-date nowadays.
If you are unable to get the latest WinRAR, please try Bandizip instead of 7-zip.
1. Check if your download is completed; open each file's download page again and check whether the filesize is consistent or not.
2. Upgrade your WinRAR or Bandizip to the lastest version; using WinRAR is strongly recommended because we compress files by it.
3. We always put 3% recovery record in each RAR file so that you have a chance to fix it yourself. Open the WinRAR main window and use "Tools → Repair archive" to do it. We strongly suggest you fix all parts in order to avoid the problem that WinRAR always says the last part is broken if some earlier parts are broken. The error message usually misleads users. In addition, please observe the filename prefix of your fixed parts. If the prefix is "rebuilt", it indicates that WinRAR cannot fix this part. If the prefix is "fixed", it indicates that WinRAR fixed this part successfully. If you still see the checksum error, it must be caused by some stupid mistakes. It usually happens when you only fixed some parts. The filename pattern of fixed files are different from the one of non-fixed files. You should rename the fixed parts and delete the corrupted ones in order to make the filename pattern consistent. Otherwise, WinRAR still extract the archive from the corrupted parts. Another possible mistake is that you are misled by the error message and you didn't fix all parts. Please try to fix all parts and extract the archive from the parts with the prefix "fixed".
4. If you are still unable to solve the problem, please let us know via the chat box. Please tell us which part on which filehost has this problem. Don't paste download links directly.