What is wrong with my orchids?

[atthelab]

Hello,

I am a novice & have a few questions regarding some ill looking orchids. I have attached 4 photos.

Questions:

Photo #1: I just "rescued" this orchid. Looks like it is rotting. The bulb (?) area is mushy, shiny & yellowing. I repotted the orchid today. Any ideas? Is it a goner?

Photo #2: I've had this orchid through 2 new growths (maybe 1-2 years). The leaves grow out wrinkled and subsequently no flower stalk is produced. What can I do to help it grown properly?

Photo #3: I've had this orchid for 5 years. It when i purchased i, did I ever see flowers, none since. The bulb area is deflated. Again, what can I do to help it flower again?

Photo #4: I've had this plant for 5 years as well. Recently it appears to have withered both stalk & leaf. Any ideas?

Thank you in advance!
(PS: Apologize for previous grammar/spelling errors!)