If you discover that you are blacklisted, the first step is to find out which blacklists you’re on and why. Then correct the problems that caused you
to be blacklisted — and ask the lists to retest your server so you can be removed from the lists.
Unfortunately, it’s much easier to get on a blacklist than it is to get off of one. Once you’ve been blacklisted, it can easily take several weeks to get off the
lists after you’ve corrected the problem.
The most comprehensive Web site for solving blacklist problems is relays. osirusoft.com
. From this page, you can enter your domain name to discover whether you have been listed on any of the major blacklists. If this site reports
that you are on any blacklists, you have to correct the problem that caused you to be blacklisted, and then ask each of the blacklists to retest your site
and remove you from their lists. Then, recheck your domain at relays. osirusoft.com
to make sure that you’ve been removed. Don’t be surprised if it takes several weeks to get removed from all the blacklists.
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Part III: Network Management For Dummies
Chapter 17
Network Troubleshooting
In This Chapter
䊳
Checking the obvious things
䊳
Fixing computers that have expired
䊳
Pinpointing the cause of trouble
䊳
Restarting client and server computers
䊳
Reviewing network event logs
䊳
Keeping a record of network woes
F
ace it: Networks are prone to breaking. They have too many parts. Cables. Connectors. Cards. Hubs. Switches.
Routers. All these parts must be held together in a delicate balance; the network equilibrium is all too easy to disturb. Even the best-designed com-
puter networks sometimes act as if they’re held together with baling wire, chewing gum, and duct tape.
To make matters worse, networks breed suspicion. After your computer is attached to a network, users begin to blame the network every time some-
thing goes wrong, regardless of whether the problem has anything to do with the network. You can’t get columns to line up in a Word document?
Must be the network. Your spreadsheet doesn’t add up? The net- work’s acting up again. The stock market’s down? Arghhh
The worst thing about network failures is that sometimes they can shut down an entire company. It’s not so bad if just one user can’t access a particular
shared folder on a file server. If a critical server goes down, however, your network users may be locked out of their files, their applications, their e-mail,
and everything else they need to conduct business as usual. When that hap- pens, they’ll be beating down your doors and won’t stop until you get the
network back up and running.
In this chapter, I review some of the most likely causes of network trouble — and suggest some basic troubleshooting techniques that you can employ
when your network goes on the fritz.
When Bad Things Happen to Good Computers
The following are some basic troubleshooting tips about what you should examine at the first sign of network trouble. In many if not most of the
cases, one of the following tips will get your network back up and running.
1. Make sure that your computer and everything attached to it is plugged in.
Computer geeks love it when a user calls for help and they get to tell the user that the computer isn’t plugged in. They write it down in their
geek logs so they can tell their geek friends about it later. They may even want to take your picture so they can show it to their geek friends.
Most “accidents” involving computer geeks are a direct result of this kind of behavior. So try to be tactful when you ask a user if he or she is
sure the computer is actually turned on.
2. Make sure that your computer is properly connected to the network. 3. Note any error messages that appear on the screen.
4. Try the built-in Windows network troubleshooter.
For more information, see the section “Using the Windows Networking Troubleshooter,” later in this chapter.
5. Check the free disk space on the server.
When a server runs out of disk space, strange things can happen. Sometimes you’ll get a clear error message indicating such a situation,
but not always. Sometimes the network just grinds to a halt; operations that used to take a few seconds now take a few minutes.
6. Do a little experimenting to find out whether the problem is indeed a network problem or just a problem with the computer itself.
See the section “Time to Experiment” later in this chapter for some simple things you can do to isolate a network problem.
7. Try restarting the computer.
An amazing number of computer problems are cleared up by a simple restart of the computer. Of course, in many cases, the problem will
recur — but then it has showed itself, and you can isolate the cause and fix the problem. Some problems are only intermittent, and a simple
reboot is all that’s needed.
8. Try restarting the network server.
See the section “How to Restart a Network Server” later in this chapter.
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Part III: Network Management For Dummies
How to Fix Dead Computers
If a computer seems totally dead, here are some things to check: ⻬ Is it plugged in?
⻬ If the computer is plugged into a surge protector or a power strip, make sure that the surge protector or power strip is plugged in and turned on.
If the surge protector or power strip has a light, it should be glowing. ⻬ Make sure that the computer’s OnOff switch is turned on. This sounds
too basic to even include here, but many computers are set up so the computer’s actual power switch is always left in the On position and
the computer is actually turned on or off by means of the switch on the surge protector or power strip not kind to the computer, but common.
Many computer users are surprised to find out that their computers have OnOff switches on the back of the cases.
⻬ To complicate matters, newer computers have a Sleep feature, in which they appear to be turned off but really they’re just sleeping. All you have
to do to wake such a computer is jiggle the mouse a little. I used to have an uncle like that. It’s easy to assume that the computer is turned off,
press the power button, wonder why nothing happened, and then press the power button and hold it down, hoping it will take. If you hold down
the power button long enough, the computer will actually turn itself off. Then, when you turn the computer back on, you’ll get a message
saying the computer wasn’t shut down properly. Arghhh The moral of the story: Jiggle the mouse if the computer seems to have nodded off.
⻬ If you think the computer isn’t plugged in but it looks like it is, listen for the fan. If the fan is running, the computer is getting power and the prob-
lem is more serious than an unplugged power cord. If the fan isn’t run- ning, but the computer is plugged in and the power is on, the fan may be
out to lunch; better shut the thing down before it overheats.
⻬ If the computer is plugged in, turned on, and still not running, plug a lamp into the outlet to make sure that power is getting to the outlet. You may
need to reset a tripped circuit breaker or replace a bad surge protector. Or you may need to call the power company. If you live in California,
don’t bother calling the power company. It probably won’t do any good.
Surge protectors have a limited lifespan. After a few years of use, many surge protectors continue to provide electrical power for your computer,
but the components that protect your computer from power surges no longer work. If you are using a surge protector that is more than two or
three years old, replace the old surge protector with a new one.
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Chapter 17: Network Troubleshooting
