Sour, rancid, or otherwise off smell
Slimy, sticky, or unusually tacky surface
Gray, green, black, or dull discoloration
Mold growth
Package swollen, leaking, or damaged
Ham feels unusually soft, mushy, or dry and hard in a bad way
Strong ammonia-like or rotten odor
Expired use-by date
Visible gas bubbles or bloating in vacuum-sealed packaging
Unpleasant taste after cooking or reheating
Stored too long after opening
Left out at room temperature for more than 2 hours
Left out for more than 1 hour if the temperature was above 90°F (32°C)