Air Conditioning - drain pipe is leaking

Preface: I know nothing about HVAC! So, please treat me like an ignoramus when replying!

The drain pipe to my indoor unit is dripping at the threaded connection. I need to diagnose the problem. I have read some threads on here that have talked about cleaning the drain pipe and pouring bleach down the drain pipe. How exactly do I do these things? I have seen it suggested to vaccuum out the drain pipe, but I would have to cut the pipe in order to have an opening where I could get a vaccuum on it. It is threaded on one end and the other end goes directly into the floor. I can't even unscrew the threaded end without cutting the pipe somewhere. And if I am going to pour bleach, where exactly do I pour it?

Any other possible diagnoses besides a clogged pipe?

Thanks,
Matt

If you have a leak in the threads that has to be fixed. It dosen't matter what you dump in the pipe, it's going to leak, maybe worse. You have to get the threaded fitting out, re-dope and put back together. Luck.

I would start by cutting the pipe & using a wet vac to try to clean out any junk. While the pipe is open, use compressed air or the blower side of the shop vac to make sure the part going into the floor is open. After making sure it will drain, dump some bleach in the pipe. A cup is plenty. To put the pipe back together, use a piece of hose & two hose clamps. This will provide easy access for future maintenance. If you have to cut out a section of pipe to unscrew it from the unit, no big deal. Just use another piece of hose & 2 more clamps. Clear hose is great but often hard to find in a size large enough. Any plumbing supply or automotive store should have hose which will fit over the pipe.
Another possible cause is a rusted out or cracked drain pan.