There are two ways to open a hosted database file and one method is strongly recommended against as it can damage your file.
Recommended: Open the file on the host computer with a copy of FIlemaker Pro or Filemaker Server installed on that computer. Use Open Remote to access that file.
Strongly recommended against: Put the file in a shared directory on a server somewhere on your network. Double click the file or use Open from FileMaker's file menu to open the file.
Using "Open Recent" could be using either of these methods depending on what method was previously used to open the file. Is there any chance that the second method has been used to open your file? If so, the file might be damaged.