I fixed a paper jam in my Imageclass D320 printer/copier which involved removing both panels and the ink cartridge to get the paper out. Now it says System Errir E100 and I can't figure out how to fix it.

On the printer properties on the computer there will be a paused option (Normally marked as "Pause Printing") in the printer drop down menu on the Printer Queue screen. Click this to remove the tick next to it and it should start printing again.

Hello,
these looks like fixing film trouble.
Change the fixing film unit - call service!!

First you have to know the position of the paper that has jamed.
the cardinal thing to do is to loosen and open doors that must be opened in order to have a clear view of the paper.
How to open see the marks on the machine. Mainly the paper jams between the drum and the fuser, so make sure you see any green nobs meant for seperating the presssure roller and the upper roller so that the paper is free to move out in case it jamed between the fixing rollers.
See the manual on how to remove paper jams.

Hello,
from the left side of machine there are door, when You open them you will have access to fusing unit, but only to the paper exit section.

To dismantle the machine you need to strip all the plastics and much more...

1. Protect yourself from shock. Disconnect the power cord from the back of the Canon Inkjet Printer. This is an important step when working inside ANY electronic device.
2. Step 2 Unhinge the back access panel of the printer. It seems repetitive to say this, but this door will be in the BACK of the printer.
   
3. Step 3 Look through the opened back panel and look for paper. Remove any and all paper you find jammed there.
   
4. Step 4 Close the back access panel. Make sure that it latches into place and looks the same way that it did before you opened it.
   
5. Step 5 Find the front or top access panel. This is the panel you would lift to change ink cartridges. Open this access panel. If the carriage that holds the ink cartridges moves, then you forgot to unplug the printer, go back and do that now. Look for paper that may be jammed in this area of the printer.
   
6. Step 6 Remove any paper you find jammed here. When pulling from the front there will be resistance from the paper feeder. Pull slowly or the paper will rip and create a more stressful problem.
   
7. Step 7 Close the front access panel. Make sure that it falls or latches back in place. It should look the same way that it did before you opened it.
   
8. Step 8 Plug the printer's power cord into the wall outlet, and attempt to print again. If the printer prints the job, then you have successfully removed the paper jam.
   

This model is noted for a jam in the fuser area around the roller, Not easy to get to but sounds a like that may be proble, Can you hear a sound like paper wrinking as it runs. Also is the drum in the cartridge clean or has tone on it. Have you changed the cartridge. I do get a kick out of Staples Experts.. They did sell you some cleaning sheets... Hey Good Luck....

depnding on which way you removed original jam you could have left a very small peice behind at a sensor arm, inspect very carfully at and before where the jam was

Sometimes what causes the problem is the black cartridge guide on the inside rear of the machine. It comes loose and so when you put your cartridge in it does not line up with the contacts properly. The parts cannot be ordered seperately. It comes with the whole rear assembly. The part # for it is HM1-0244

laser printers dont use ink.
you will have to check the sensors. first the one where you put the media (paper) then check the registry one (remove the cartridge and you should see it) then the fixing on, from the back it has a small cover you can open an dthen a pair of green coloured levers to remove any jammed paper in fixing (the hot ***'y) then check the delivery sensor right where normally you see the page printed out and coming your way. there should not be any media remains anywhere. also if you copier is dirty it may also be causing this. try to clean it with compressed air.

Step1
Turn the printer off and on to see if it can automatically clear some or all of the jam. Many printers provide an error-code listing on the front panel display for the area where the jam occurred. If your printer shows an error code, be sure and check the printer manual to see if that identifies the area of the printer where the jam occurred. 
Step
2
Turn off the printer. 
Step
3
Remove any paper trays. Inspect them for wrinkled or damaged paper. 
Step
4
Open any other doors that give access to the printer's paper path and to the toner or ink cartridge. 
Step
5
If necessary, remove the toner or ink cartridge. Place it in a bag or away from light to avoid damaging it. 
Step
6
If you find a piece of jammed paper, remove it by holding it with both hands and pulling firmly (see A). The goal is to keep the paper from tearing. If several pieces are jammed together, try pulling out the middle piece first to loosen the jam. 
Step
7
If the paper does tear, try rotating the roller gears manually to free the paper (see B). Don't force anything, though. 
Step
8
Replace the toner or ink cartridge and paper trays, close any doors you opened and turn the printer back on. 
Step
9
If the printer paper jam message still appears, then there is still some paper in the printer. Reinspect the paper path.