With Bosch, each one is tested at the factory before they leave. I have purchased two and both were wet when delivered.

It is Bosch. I’m worried about mold because now I saw small black dots on the racks and the string with the paper

inside is also black. It smells like towels that have been left wet for a while. Thanks for your feedback.

I have a Bosch and it did not have black of any kind on the interior nor exterior nor did it stink upon arrival. I would ask for a replacement because of what sounds like mold.

Run a cycle with a dose of chlorine bleach added to the main wash period.

My Bosch came wet and smelled and the bottom tray wheels were squeaking probably from being wet for so long. No black stuff, but ppl say it's wet when it leaves the factory. Mine had a sticker on it from July and I got it in October so I suspect it was wet for a long time. Anyway it's been running fine.

use the product to clean dishwashers , you can find it at the grocery store, follow the instructions

Most dishwashers are tested at the factory, some residual water is normal. You can run it through a cycle or two using a dishwasher cleaning product. See if the odor goes away after doing this. We did have one where it smelled like something had died in there and would not go away, after numerous complaints they replaced it.