10 really dumb mistakes to avoid in the field

Certain mistakes are almost guaranteed to result in problems that can cost you clients. Make sure you don't fall prey to these common missteps.

We all do it. Make mistakes. Some of them are just little DOH! moments that lead to embarrassment. Others, however, lead to disgruntled or (worse) lost clients. Many of those mistakes can be avoided if you know what to watch out for. I'm going to highlight 10 mistakes you don't want to make when you're on a job. Avoiding these mistakes will help you retain your dignity — and your clients.

Note: This article is also available as a PDF download.

1: Don't blindly upgrade

How many times have you upgraded Windows XP to SP3 (including IE8) only to find out (postmortem) that something in the upgrade has broken some feature or functionality your clients need to do their job? I have seen this far too often. Internet Explorer 8 is notorious for breaking currently working systems. Make sure you know the critical sites your client needs to use and confirm that they work with IE8 before undertaking any upgrades.

2: Don't edit configuration files without backing up first

This can get really tricky when doing things like migrating Linux servers from one machine to another. Make sure you are clear what's a backup and what's a currently working configuration file. Do not let these files cross paths (nor their filenames). Get into the habit of copying and renaming backup configuration files so you know exactly where that working backup file is.

3: Don't forget to turn the firewall back on

You know you've done it. You can't seem to get a network function or feature to work so you shut off the firewall to remove one possible hurdle. In your excitement (after you've nailed the problem), you leave without turning that firewall back on. Bad move. Before you leave that desk, make sure that the firewall is back up and running so that machine is protected.

4: Don't forget to document

How many clients do you have? If that number is more than 0, you need to be keeping documentation on those clients. Having to navigate around the network to discover the lay of the land wastes time. Keep a good record of passwords (unless you prefer to entrust them with clients to preserve your own liability), network addresses, machine names and functions, etc. The more the better.

5: Don't do anything without client permission

No matter what you're working on, you want to make sure the client has given the okay for the job. Think about it this way: Any work you do without client permission could easily be work you won't be getting paid for. Or worse, you might undertake a task (without permission) that could cause data loss, which could lead to much bigger issues with regard to the bigger picture.

6: Don't experiment on a client machine

You might be tempted to try that new "fix" you heard of that can shave a few minutes (or hours) from your job. Don't. Test those hot new fixes either in the office or offsite. Don't trying something unproven unless you are 110% sure that this fix will work for the situation you are about to use it in. And if you do attempt it, make sure you have a backup of the system before you do.

7: Don't learn on the job

This relates to number six (sort of). We can't know everything. On a daily basis, we run across something we've never used or seen before. When you come across something you know nothing about, don't try to learn about it on the job. Those clients aren't paying you to learn; they're paying you to fix. If you have to research a piece of software, tell the client you will need to do so and you will return when you're ready to tackle the issue. If the client is okay with your learning on the job, do so. Just make sure they're aware that what they are asking is beyond the scope of your knowledge. It's always better to be honest than to try to BS your way out of a situation.

8: Don't use Add/Remove Program to uninstall antivirus

Recently, we had a machine come into the office with FOUR different antivirus apps installed. Needless to say, the machine was nearly unusable. All four pieces of antivirus software had to be removed and, fortunately, we were smart enough to use the included uninstall for each one. When using the Windows Add/Remove Programs tool, the antivirus will leave behind traces that can cause problems for other antivirus tools. Just be safe and use the included uninstall tool for the software.

9: Don't go in without knowing the situation

Unless you're visiting a new client, one of the most unprofessional things you can do is to go into the situation without knowing what's going on or what the layout is. If a fellow employee is about to hand off a client to you, make sure that employee gives you the lowdown on the layout of the network topology, as well as point of contact information and any special information regarding the installations, users, or system quirks.

10: Don't leave the site without making sure everything works

You might think you've covered everything. And everything may work from your perspective. But that's not enough. Sit users down at their computers and make sure things work from their perspective. They are, after all, the ones who have to use the computer. If the machine doesn't work according to their expectations and needs, your work is not done.

Other missteps?

The last thing you want is to make one of the above mistakes. Letting yourself fall victim to anything you've just read could cause you to lose respect and clients. Don't let this happen.  What other mistakes should go on this list? Have you made a mistake you hope to never make again — or seen other techs get into hot water over a botched job?

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Jack Wallen is an award-winning writer for TechRepublic and He’s an avid promoter of open source and the voice of The Android Expert. For more news about Jack Wallen, visit his website

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