I have a 750il E32. I was getting all P's on the OBC display. I was told I needed to replace the OBC. I got a new one and it also had the pppp. Do i have to reset it?

There have been several thread on the PPPP error. Have you set the time and date yet?

http://www.nmia.com/~dgnrg/page_35.htm
From my website below
http://www.hyrumswebsite.com/BMW_pdfs/OBC_info.pdf

I tried to find some of those threads but was not successful.

Just read what I linked, that is enough.
As fermunky mentioned, set date and time new, in case battery was disconnected.
If that does not help, remove the OBC, spray electric contact spray onto the sockets and plugs at the rear of the OBC, then connect again and see what happens.
How to remove the OBC is shown in the link above to Gale's website.

tried it to reset but it didn't work, my biggest problem is the car is at my brother's house now, i gave it to his son. I am trying to tell them everything to do over the phone

pushing the S/R button did not reset the pppp. I have asked him to go buy some contact spray and try that. He bought an obc for it but its doing the same thing.

Whow, that is more difficult. So we tell you what to check and you tell them what to do via phone, I hope that at the end the same is understood ;)

Anyway, the idea to remove it and spray contact spray on the back socket and the plug is good. Lets see what they report.
But I am a bit worried that they do not understand how to get it out, or that they break the lever of the holder.
Wish them good luck.
But better send them this instruction
http://www.hyrumswebsite.com/BMW_pdfs/OBC_info.pdf

Maybe you print it out and send it by mail, if they do not have interneyt connection, is anyway not that urgent, car runs also without OBC.
Check if the cables are all secured at the backside.

Here is a good instruction how to remove the OBC
http://bmwe32.masscom.net/johan/OBC_bulbs/OBC_bulbs.htm

One more thing just came to my mind. The PPPP can also mean that the OBC cannot get any data from the chip on the cluster. Remove also the cluster and spray also those 4 plug contacs.
The assemble again and push the stalk next to the steering column and see if the OBC data are shown on the check control at the bottom of the cluster. If that works, the connatction between OBC and cluster works and the OBC is the problem, if it does not work, transfer of data from chip is interrupted. They should look into the owners manual to see how to get these data.
Removing cluster without airbag
http://bmwe32.masscom.net/sean750/dash_bulbs/changingClusterBulbs.htm

I remember Bill R (bimmer dot info -- e34 board) mentioned sometimes the OBC needs to be "hot swapped" meaning turn the ignition to position 2 and then plug in the OBC live so it can sync with the instrument cluster.

Mine has shown pppp a few times when messing with it and hitting the s/r always corrected it. One time I found a few of the pins bent over from a fumbled install and had to take it out and straighten them but that time it was completely dead with no display at all. If you can't get it to snap out of the pppp, then maybe the replacement is also bad?

yes, that could also be that the pins bent over when they installed the new bulbs.
Bill R. is a professional and he has his own repair shop. I like his comments and also his repair tips very much.
I am in contact with him often.
For example he made this for airbag and bulb change in the cluster
http://lehrmangroup.com/rickard/airBagAndBulbs.html