When trying to restore a Postgres backup, you may get this error:
Unsupported version (1.13) in file header
You get this because of two reasons:
You have backed up the database with a different version of the PGAdmin software than the one you are restoring with
Postgres hates you
You might try to back up the file as a SQL file or some other method to read it in, but that won’t work. The only way that I have found to work is to backup using the same version of PGAdmin that you plan to restore from (note: the database doesn’t have to be the same version). For example, backing up from PGAdmin 3.0.2 and restoring from 3.0.1 won’t work, but doing everything from PGAdmin 3.0.1 or 3.0.2 will work.
If you are in a position where you don’t know what version you backed up from, there may be a clue if you open the backup file in Notepad++, depending on the type of backup you took. If you are trying to find a specific version point of Postgres / PGAdmin, I refer you to point #2 in the list of causes of the Unsupported version error. Good luck!