What are my responsibilities as a tenant in ensuring my landlord receives rent on time?

Rent at my complex is due on the first of the month. Recently, the (new) management company cut back office hours from standard 9a-5p, Monday-Friday to only being open 9a-noon, Monday, Wednesday, and Friday. I paid the rent using the drop box -- which is what I was told it is to be used for -- during my lunch break on March 1st.
Today, March 6th, I receive notice on my door that unless I pay rent plus a $100 late fee by March 9th, I will be served with eviction papers. I attempted to call the number on the paper, and was met with 10 rings followed by the standard, "we value our residents and are not available, please leave a message."

My options at this point seem to be 1) take time off work to go in person tomorrow morning during their limited hours, 2) drop yet ANOTHER check in the drop box and hope they get that one.
Is this an issue of good-faith on their part?

I have no problem giving up an hour to deal with a problem. Which is why I went in this morning, before work, only to find a note posted on the door stating that they would not be back until Monday -- the 12th -- 3 days AFTER they are requiring payment. Fortunately, I ran into the maintenance guy, and he said he'd vouch for me that I was there. I also took a picture of the sign on the door in case I should need it.

Wait a minute. You paid the rent on the first. Why are they looking for another month's rent PLUS $100?

Read your lease. Usually there's a "grace period" before they hit you with a fine. It should also have a provision regarding the lockbox.

Also, read up on landlord/tenant law. Sometimes even if you agree to a rental term in writing, it's unenforceable at law. Go to your county courthouse (or google) and ask the housing section clerk for any publications they have on landlord/tenant law. (See below for a sample from CT).

In any event, if they provided the lockbox for tenants' use, it's up to them to check it. Rents are deemed paid when delivered, not received. If they say they didn't receive it -- do your best to prove you wrote and delivered it, like show them a copy of the stub or ledger entry, -- but put a stop-payment order on the "lost" check before you replace it.

I'd tell them to go pound sand up their @$$3$.

If you really paid your rent on the 1st then obviously they didnt get your check/m.o. What happened to it? Has it cleared yet? You need to go in person and find out what happened.

Give them another check if the first one has not cleared. In the future, I would spend $4.05 and mail the check to them through US Priority Mail. It is better to have proof that they got it instead of giving them $100 because they lost it.

Sounds like you're technically "right", but sometimes that really doesn't matter. Find out what happened to the first one..it could be something you don't know about..forgot to sign, fluttered away from the collection box and under a piece of furniture...anything. You live there under a lease I assume now...so you're stuck for a while...just do what you can to make sure it doesn't happen again..even if it's not your "fault", take your lunch early so you can pay before they close at 12 (a day or two early if you need to) if you mail it you can get proof of delivery..but you still have to mail it ahead of time..and it might be delayed.

Now..I'd call and find out what's going on during their office hours..and then go see them if necessary. Politely..let them know how inconvenient it is..they may have a complaint form or something that would get the word up..and they probably can't do anything about it anyway.

Well, I think if you were all that concerned about it and you really had dropped off the rent check, you would take an hour off and go get this straightened out.....unless you don't mind being evicted.