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My System is Running Really, Really, Slowly

This one drove me crazy for days. It seemed that every time I went to a particular folder, my system suddenly began working at 1/100th of its normal speed. It was beyond sluggish, it was practically dead. I thought at first I had a virus, but rebooting and running a virus scan cured me of that notion.

The problem was that the folder contained movie files with an .AVI extension. Windows Explorer looks at the first few bytes of each AVI file to obtain the dimensions of the film (X pixels wide by Y pixels high). It does this for no apparent reason. It is possible for you to specify the dimensions as one of the column headers in the Explorer window, but it does this even if you have not done that.

AVI movie files are encoded with an algorithm called a "codec", which is short for "encoder / decoder". There are dozens of codecs, but the most popular ones are MPG2, MPG4, DivX, and Xvid.

If Explorer doesn't recognise the codec for a movie, it should either ignore it (which is what it does for other file types, like TXT), or put out a diagnostic, such as "unknown codec for file xxxx.avi". Instead, it starts reading the movie file, byte by byte, looking for a codec. Movies can be 700MB or more long. Worse, Explorer consumes 100% of the CPU time, which you will see if you can start the Task Manager and look at the processor performance. This is why the computer suddenly becomes sluggish, Explorer is consuming all the available processor cycles.

Why does it do this? Some stupid programmer at Microsoft wrote it this way.

When did this bug first occur? 2002, it's part of the Windows XP Explorer basic code.

When will it be fixed? Never. Microsoft does not fix bugs.

What can you do about it? Download and run a program called "Gspot", and use that to check each AVI file. Gspot will tell you what codec the file needs and whether it is installed. Then use Google to find and download the missing codec.

You can get Gspot at http://gspot.headbands.com/. It was written by Steven Greenberg and is free.

You can also go to a DOS prompt, navigate to that directory, and then rename the file to another extension (other than AVI or MPG or MPEG). Then Explorer won't look at it.