We had a harddrive failure last month and was forced to reinstalled 2000 A/S and Exchange server. The problem is, when the system asked for a domain name, I entered RJB.local - not knowing the system would go to the internet for RJB.COM (the company I work for is RJB Financial). Now my clients are having a problem accessing Exchange and we often have to hit retry a number of times before we log on.
Additionally we get the following error - The session setup from the computer RICHNOTEBOOK failed to authenticate. The name of the account referenced in the security database is RICHNOTEBOOK$. The following error occurred:
Access is denied.
Any guidance would be appreciated.
thanks

There were some assumtipons in your posts. The Hard Drive that crashed was the ONLY Somain Controller in your old Domain is the first presumption.

If that's the case, then a NEW domain, with a new Domain controller (unless you use disaster recovery process to restore a system state and Volume Information) produces new GUID's and Security Descriptors. All previous User accounts and computer accounts are invalid.

After yuu reinstall windows 2000 and Active Directory all of the computers have to be rejoined to the NEW active directory domain. Active Directory's foundation is based of DNS resolution. All internal systems which require access to network resources must be able to find the Domain Controller first - then the Internet if a requested resource is not internal.

So, DNS must be up and running internally, then forwarded to the ISP's DNS (oresuming you have internet Access).

See Articles :

HOW TO: Configure DNS in a New Workgroup Environment in Windows 2000
Microsoft Knowledge Base Article - 301197

HOW TO: Configure DNS for Internet Access in Windows 2000. Microsoft Knowledge Base Article - 300202

HOW TO: Create a New Zone on a DNS Server in Windows 2000. Microsoft Knowledge Base Article - 308201

You need to configure DNS internally for
RJB.local (internall) with a forward and reveerse DNS ZONE. Then All of the PC on your network well most likely have to be disjoned and rejoined to the New Domain Controller.

See Microsoft article :
Netlogon Event ID 5770 and 5722 on Primary Domain Controller

After all of this users can authenticate faster, as long as their DNS IP is that of the new rebuilt internal Domain Controller (as oppoed to directly to the internet Address) and that their joined to the new Domain as well with valid computer accounts.

Good Luck