Oh, it's working now. How embarrassing.

You probably wouldn't be surprised by how often I arrive at a job only for there to be "nothing wrong".

The reason I had been called has disappeared as mysteriously as it arrived.

It is a common joke that the computers can smell me when I arrive and choose to behave themselves to spite their owners.

When the problem fails to manifest when trying to reproduce it people are embarrassed and annoyed.

You needn't be. It is common. It happens a lot.

We do still need to have a bit of a ferret around to see what may have happened and how to prevent it happening again.

BECAUSE, you can bet that as mysterious as its disappearance was with my arrival, its return after my departure is nearly as assured.

Automatic updates are a common cause for all sorts of problems.

They're supposed to fix things, patches bugs and security flaws, but sometimes the installation process isn't as seamless and invisible as we'd like or assume AND sometimes they just make things worse.

When Microsoft release their major updates they are quite large and sometimes so is the duration of "weirdness" they cause for the behaviour of your computer.

These large automatic updates happen "in the background" and can often span days.

It's not uncommon for people to endure issues, call me, drop the machine off and everything be "OK" when I turn it on.

You see, often full powerdowns (hard reboots) give these updates a kick in the pants...or cancel them only for them to try again in a few days.

Of course there are also environmental factors. The physical and location based things that are, by their nature, remove or changed with the relocation of a machine in space or time :-)

• Things like cables failing. They look like there's nothing to go wrong. But there is and they do.

• Things like buying a new appliance for the kitchen and suddenly your wifi stops working.

• Things like your internet dropping out with the change of season...

• Your computer crashing more often at one part of the year over another.

• Things like the computer not working in one room, but starts fine in another room...

• and so on...

There's an old and apparently apocryphal story about a car that would or wouldn't start depending on the flavour of icecream its owner bought after driving to the local store.

While it may not be true, I have encountered problems very, very similar to this.

The story is a good reminder that the weirdest things can be related to the weirdest problems and that making assumptions about causes can be very, very flawed.

It is also worth noting that just because it doesn't happen again, it doesn't mean it didn't happen at all and the warning is not worth heeding.

One of my frustrations as a software tester was software developers denying the existence of problems.

There's an old joke that clarifies why this is a problematic attitude:

A software tester and a software engineer were driving in a car.

On a particularly steep hill, the car’s brakes failed.

The car rocketed down the hill at terrifying speed and wound up crashing into a ditch.

The software tester jumps out of the wreck and shouts "Did you see that? Did you see that? We crashed. Oh my God. We're lucky to be alive!"

The software engineer says “Hmmm, I'm not sure. Let’s push it back up to the top of the hill and see if it happens again”.

It isn't always possible to solve these mysteries in the short time I have with you, so you may want to keep a diary or a log of when things happen and what else was going on at the time.

The log should include how you are doing things. What you did just before encountering the problem and any changes in environment you can think of.

Put as much detail into it as you think is required to overcome the pain you are experiencing :-)

If a problem just happens for you, and not for me, embarrassment aside, this is good news. It means we have a workaround for your issue i.e. a different way to go about things that bypasses the issue.

Sometimes these problems can take a very, very long time to solve.

Sometimes it is a happy accident that reveals the truth and gives us a way out.

One of the longest running and most frustrating issues I helped a customer with was intermittent NBN dropouts over months and months.

As you can imagine the NBN Co weren't all that helpful.

The ISP had sent a couple of new modems of differing types and each exhibited the same problem...which meant it was probably something else.

At one stage a helpful NBN engineer, talking out of school and off the record, said that "we've had some of these towers move with the heat and wind. Just enough to stop people's internet from working on and off".

This sounded interesting but the pattern didn't match what we were experiencing.

We'd all but decided to live with the issue when I had to crawl under the desk for another reason.

It was then that I spotted a box with flashing lights on it that I hadn't seen in years.

It was a wifi extender that connected to an out-building, but it was no longer needed.

It had been running all along and had been working fine.

However, now no longer having anything connecting to it, I decided to switch it off and remove it from the network.

You guessed it, the problem went away!

The old wifi extender was incompatible with ALL the new modems and routers the ISP had sent. It worked with the old ones but effectively jammed the new ones every time it tried to connect to the out-building that was no longer answering...which happened to be every 10 or 15 minutes. Argh!!!!

So, much like the Ghostbusters, make sure your computer help person is ready to believe you.

Have fun, David