A photocopier may run for years without giving you any problems, but when it does start to break down, you may feel as if you're entire business has come to a standstill. You can't have clients sign paperwork if you can't make copies of it, and someone may be delayed in your office because of needing copies of their agreements, lease, or other papers. Before you call a technician, you might try a few troubleshooting tips on your own; these can also tell you what you might expect by way of needed repairs to your machine.
Shadows along the copies
If you've cleaned the glass of your photocopier but still get shadows and smudges or any other spots along your copies, it may be that you have a toner leak inside the machine. If the toner is getting out of the drum where it's contained, it may be brushing against the copies as they go through the area where they're processed. Your machine may need a new drum and a thorough cleaning inside, to remove any toner from internal parts.
Paper jams before copying
Note if the paper jams before it has any copying on it; if so, this can be a problem with the roller that feeds the paper through the machine. Check the cassettes where the paper is held and you should see a small arm with a roller or set of rollers that engage when you make a copy. If those rollers are damaged, the paper won't get fed through very easily and may jam before a copy is even made. That arm or roller may simply need to be replaced.
Machine shuts down
If your machine shuts down in the middle of an operation, this often means that it's simply overheating. Many photocopier machines have an internal control that shuts them down automatically when they get too hot, to avoid damaging internal parts. You may not realize that your photocopier is programmed to do this. To avoid having it shut down, use a sleep mode when it's not in use; this means it's using less power to run the front panel and other parts, so it can cool down. Be sure it's not up against a wall, as this can mean little air circulation around the parts inside and, in turn, the machine gets overly warm when it's used. It may seem like a small thing, but ensure that the machine is not under a window with direct sunlight or near a heating vent, as these too can cause it to overheat unnecessarily.