SP6 Update
As of October 10, Windows NT 4.0 Service Pack 6 (SP6) is still not available for public download, although Microsoft might have distributed it privately to selected customers. After last week’s column, I received some updated information about the post-SP6 Rasman hotfix (Rasman-fix) from a program manager on Microsoft’s Security Incident Team. First, the hotfix won't be in SP6. Second, because Rasman-fix changes only the rasman.exe ACL, you can apply it to SP5 or SP6. If you apply it to SP5, you don't have to reapply it after you upgrade to SP6—SP6 will preserve the corrected ACL. Unfortunately, the Rasman security bulletin at http://www.microsoft.com/security/ bulletins/ms99-041.asp doesn't document any of this information, and Rasman-fix isn't included in the post-SP5 hotfix directory.

According to the rumor mill, the Microsoft testing team discovered regression errors in SP6 last week, and thus, the company might push back the SP6 release date until it corrects the errors. I've also heard additional rumors of an SP7 on the horizon, but I haven’t heard of a possible release date. Maybe we'll actually make it to NT 4.9!

Print Spooler Bug Fix
After I wrote up the instructions on how to flush a lingering "delete print job" from a print queue with the Net Stop Spooler and Net Start Spooler commands, several readers informed me that the procedure doesn't work all the time. And so, with a big grin, I'm happy to report that Microsoft Support has a new print spooler (spoolss.exe) that purports to correct the problem. According to Microsoft Support Online article Q243222 (http://support.microsoft.com/ support/kb/articles/q243/2/22.asp), this update corrects print spooler startup problems that report "A system error has occurred. System error 12 has occurred. The access code is invalid." Hooray!

RPC Server Unavailable or Too Busy
I think every Windows NT systems administrator has seen the "RPC server unavailable" and "RPC server too busy" error messages repeatedly, possibly for years. Sometimes the errors mysteriously disappear, and other times we have to take corrective action. Here are several situations that generate these messages—you might want to keep these descriptions handy so you’re ready the next time the RPC server goes out to lunch. In general, the RPC server reports itself as unavailable when it needs to talk to a specific NT service and that service isn't running.

On a backup domain controller. Aaaah, more WINS issues—and I don’t think we’ll get rid of them until Windows 2000 (Win2K) has been in production for several years. Occasionally, NT doesn't register two NetBIOS entries for a domain controller: the 1Ch domain controller name and the 1Bh domain master browser name. When the names are missing or the OS improperly registers the names and a BDC attempts to contact the PDC, you might see this message:

   Event ID 5719
   No Windows NT Domain Controller is available for domain <domainname>
   The following error occurred: RPC server is unavailable

To correct the problem, you need to correctly register both names in the WINS database, purge and reload the NetBIOS name cache on all BDCs, and replicate the WINS database updates to all WINS replication partners. Article Q242121 (http://support.microsoft.com/ support/kb/articles/q242/1/21.asp) contains detailed instructions on how you create an LMHOSTS file with the required name entries on each BDC, import LMHOSTS into the WINS database as static mappings, replicate the name entries, and flush the name cache.

When running IIS 4.0 and 5.0. When you install Microsoft Internet Information Server (IIS) 4.0 or 5.0, you administer the Web server via the Microsoft Management Console (MMC). If you stop the IIS Admin service, you’ll see the error message "RCP Server is unavailable." To correct the problem, start the IIS Admin service. Microsoft Support Online article Q240311 (http://support.microsoft.com/ support/kb/articles/Q240/3/11.asp) documents this issue.

When running the Specified User utility. Do you make use of the Microsoft Windows NT Server 4.0 Resource Kit Specified User (SU) utility? If you first install version 2.0 and then update it to version 2.99 from supplement 3 of the Resource Kit, you might see the same "RPC server is unavailable" error message. According to article Q242050 (http://support.microsoft.com/ support/kb/articles/q242/0/50.asp), you can correct the problem by removing four rights from all users and groups: Act as part of the operating system, Increase Quotas, Replace a process level token, and Restore files and directories. After you remove these rights, you need to reinstall the most recent version of SU from the command line (suss.exe-install).

When adding a printer. Boy, we've seen a lot of print spooler issues recently—the list keeps growing, and here’s one that causes an "RPC server unavailable" error message. If either of the print spool components (spoolss.exe or spoolss.dll) are missing or corrupt, you’ll see the error message when you attempt to add a printer. To correct the problem, you need to reinstall either or both of these files from the original distribution media, reapply your most recent service pack, and verify that the RPC service is set to start automatically. Microsoft Support Online article Q242079 (http://support.microsoft.com/support/kb/articles/q242/0/79.asp) documents the corrective procedure.

When running License Manager. If you ever see the error message "RPC server is too busy" when you run License Manager, there are two potential sources for the problem: either the system has lost network connectivity or the License Manager database is corrupt. First, try to stop and restart the License Logging Service. If this procedure doesn’t correct the problem, you might have to delete and recreate the License Manager database—recreating the database is simple when you have only one or two servers. When you have more than a couple servers, you have to manually clear the database on each system, a complicated procedure. After you delete the database, you need to reboot each server that has a registered Microsoft application such as Exchange or SQL Server installed to ensure the application registers itself properly in the License Manager database. See Microsoft Support Online article Q204018 (http://support.microsoft.com/ support/kb/articles/Q204/0/18.asp) for more details and references on how to recreate the license database.

While running DNS Manager. According to Microsoft Support Online article Q189007 (http://support.microsoft.com/ support/kb/articles/Q189/0/07.asp), you’ll see the "RPC server is unavailable" error message when you start DNS Manager, connect to a remote DNS server, and the DNS service is not running on the remote system. The fix is simple—start Server Manager, connect to the remote system, and start the remote DNS service.