A new member has posted over on the Ask A Question Forum and needs help with a cactus. I thought maybe some of you who are more familiar with cacti might be able to offer advice. You can view his question and see the photo of the plant here: The thread "Cactus health" in Ask a Question forum

Thanks in advance for any advice or tips you can give him.

Looks like body tissue rot to me, tell him to have his girlfriend leave the plant alone in watering and spay with an anti fungus rot spray.

it may have to have surgery/ you cut out the rotting part then spray to save it.

cacti are useally a group that hates watering freely of any kind