I'd agree it's the humidity. Something is growing under there.

"I am thinking about putting foam sealant around the pipes to fill in the little holes."

Why are you putting it off while asking questions? What possible harm might it do?

Let me get this timeline straight...

This thread where you complained about the smell was from July 24th.

Original complaint

Then you left the cabinet open for 2 weeks.

Then you waited a few days and noticed that it smelled?

Then you waited almost another month before posting this question again?!?

You really don't like to act quickly, do you? :)

See if you can find Damp Rid with charcoal. Place a container in the cabinet and see if that will help.

None of this, however, is going to take care of the root cause of the problem. That's what you need to find.

I just want to add that I had a problem that sounds very much like yours. Damp Rid with charcoal has cleared the problem smell up. We bought an older home and live in a hot, humid climate.

Yes it may clean up or eliminate that smell but it does not get to what caused the problem. In the op's case she went the lipstick on the pig and low and behold the lipstick wore off and the wound reappeared......

All I can say is if the op lives in a hot, humid climate like I do, you cannot clean up hot, humid climates and you cannot fix a hot, humid climate. It is an issue that those of us who live in it have to deal with all summer and into fall. However, I have no idea where the op lives but was just commenting from my own personal experience.

I definitely cannot help the humid climate. There may even be some rotted subfloor under the cabinet. I will just spray the foam sealant in the open areas around the pipes. I have a bag of damp rid and have used it but since it is so humid under there all the crystals disolve in one day and it s kinda a pain to keep empting out the container and adding more crystals.

I think we are more worried about the condition of your crawlspace and your floor joists. If they rot out over time because you never checked them or resolved a problem down there, then your floor will fall in.

Definitely seal up your house so air doesn't penetrate in, but also inspect your crawlspace some day.

The crawlspace was inspected back in February. There were a few problems bbut nothing major. There is a huge rotted out section in one of the joists under the bathroom, but i will have that fixed in time.

until you know what is going on at the floor level

you are just band aid-ing the problem.

go under the house & see what the area looks

like. is it rotted? water damage?

from where does the problem (the problem

with the symptom of the smell) originate?

fix the problem &

the smell will go away.

best of luck

Do you have a dishwasher?

When I lived in Baton Rouge, LA in a house with two bathrooms over a crawlspace, I learned - after living there for about 3 years - that the bathtub we never used except to bathe the dog had a broken drain pipe. It emptied into the crawl space. The only way I learned this was that I just happened to open the water heater closet while the tub was emptying. The closet had a screened opening in the floor in order to provide fresh air for the gas-fired appliance, and I could hear the water splashing onto the visqueen (plastic) on the floor of the crawlspace. When the plumber went down there to reconnect the pipes, the missing connector was not there, so he assumed that the guys who installed the visqueen before we closed on the sale of the house must have knocked it off and it got lost under the visqueen sheets. There was only a small lake from washing the dog, luckily! I think we just left vents open so it could dry. I was so lucky that I happened to go into that utility closet that day, or we would have used that shower daily a few months later, not knowing there was no plumbing connection.

You could have a leak or a similar plumbing issue. You do say that the crawlspace was inspected, though. If the cabinet that smells was one that had the mold in it when you moved in, it may be that you will have to sand it and paint or seal it in order to get rid of the smell. Some of us can really smell certain molds that are not obvious to others. Be sure to wear a good mask or respirator when you sand.