The only way to "fix" this issue is to replace your user profile with a profile that has all the unlocks already.
Base 10 decks fully unlocked: 97330 (base decks).zip
Base 10 decks + 5 expansion decks fully unlocked: 97330 (expo).zip
Base 10 decks + 5 expansion decks + deck pack 1 decks fully unlocked: 97330(deckpack 1).zip
Base 10 decks + 5 expansion decks + deck pack 1 decks + deck pack 2 decks fully unlocked: 97330(deckpack 2).zip
Base 10 decks + 5 expansion decks + deck pack 1 decks + deck pack 2 decks + deck pack 3's Rogue's Gallery fully unlocked (Mana Mastery and Sky and Scale refuse to save due to a glitch, if you want Sky and Scale then use the download above but you miss out on Rogue's Gallery so you need to pick which deck you prefer. I'll upload a save file with all unlocks when/if Stainless fix this glitch): 97330 (minus Mana Mastery).zip
Go to your user data directory eg:
C:\Program Files\Steam\userdata\YOUR USER DATA NUMBER HERE
And delete or rename the folder called "97330" and replace with the folder and files in 97330.zip.
Now the file called "YOUR USER DATA NUMBER GOES HERE.profile" needs to be renamed to your user data number.
Now you need to disable cloud sync. Go to library in Steam, right click MtG DotP 2013, go properties, under the updates tab uncheck the "Enable Steam Cloud sync" box.
Run the game, you now have all decks with full unlocks.
Remember to make backups of your user profiles in case you mess up and lose your data.
You will NOT be banned for this, DotP doesn't even use VAC.
There is NO way for you to get your old save profile back, it is gone forever.TEMP FIX FOR MANA MASTERY AND SKY AND SCALE UNLOCKS