Careful record keeping is essential to successful troubleshooting. You should have records of your network layout, cabling, previous problems and their solutions, dates of installation of hardware and software, and so on, all readily accessible. (Remember that you can add your own notes to the Messages database that is included with Windows NT and with this Resource Kit.)
Many problems can be avoided with routine virus checks. You should make a special point of checking for viruses before installing or upgrading Windows NT on a computer that is already in use.