When we restart our oki c5700 we get the fatal error 928. Can you help me to solve this problem?

Just to confirm that Jeff Hughes is correct. 928 does refer to paper wrapped around the fuser rollers making the thermistor see nothing hence the 928. If there is no paper in the fuser then it will need to be replaced. Remember to turn the machine off when removing or replacing the fuser.

it means FUSER MOTOR LOCK ERROR call a tech or you could try replacing the fuser motor

Error 928: Fuser Motor Lock Error An error was detected with Fuser Motor rotation by overload. If rebooting the machine does not improve the symptom, you need to check the Fuser Unit.

Thons is an issue with your computer (Windows right?)Try To do a registry cleaning with a free registry cleaner.

Fuser Motor Lock Error The fuser is not operating properly
Check to confirm that the fuser
is in position.
Replace the fuser.
Replace the fuser motor.

This is a fuser motor lock error. Check that the fuser is installed normally. You may need to replace the fuser unit or the fuser
motor.

TRY REMOVING ALL CONNECTIONS & THEN RESTART.REMOVE CATRIDGE AND RECONNECT

A drum can print only a limited number of pages before failure - your drum has reached that number and must be replaced.

1. Turn machine on while pushing and holding the TWO up/down menu buttons at same time.
2. Menu window will show "OKI USER"
3. Scroll to " Engine Dialog Mode" is indicated. Push Enter button.
4. "Diagnostic Mode xx.xx.xx S-Mode is indicated.
5. Scroll to "NV-Ram initial" is indicated. Push ENTER.
6. Window shows "NV-Ram- Initial Table 1".
7. Push ONLINE and ENTER Buttons simultaneously and HOLD for 10 seconds after you see "Executing Reset" appear in menu window.
8. Restart printer.

928 - fuser motor lock error

take out fuser and check for paper stuck on roller
make sure roller can move

if roller is stuck or damaged, repalce fuser unit