Absolutely. Using DB Commander, open players.dbf and locate the player you wish to edit. From there, it's just a matter of changing the NUMBER field. The values are simply the exact numbers you wish to assign from 0-99, if you want to assign number 00 then you must use the value -1.
Since you're editing databases associated with a Dynasty, it's a good idea to make a backup first in case anything goes wrong.
Andrew man i don't know how to save the file and it didn't change it.The DB Commander from the site i can't download if you know from where else can i please tell.And do tell step by step if you can please??
Andrew man nothing happens again.I change the number and i exit the program the number stays as i changed it,but when i go into the game the number is not changed.Any Ideas why is this???
That's really odd. Once you reload the Dynasty game, the changes should be there. The only other possibility is that you're editing the wrong file, since if the changes are being saved in the database - which they obviously are, if you open it up again and they're still there - once the file is reloaded in the game, they should show up.
Are you editing your own players or those on CPU teams? If it's your own players, there's two entries in the databases since one is used as a comparison in the Player Development display between seasons. Make sure you change both. Of course, if you're changing the jersey numbers for your own players, you can just do that within the game in Edit Player (you can edit your own player's jersey numbers, accessories and primary/secondary positions in Dynasty Mode).