This is not necessarily a very big problem. A Com Overrun happens when your computer has to ask your modem "what did you say?" There are a few reasons why you will get these.

• You have an external modem but only have a 8250 com port. You must use a 16650 com port with a 14400bps or 28800bps modem.
• You are using Windows 3.1x which was not really designed to work well with fast modems. Upgrading to Windows 95 will solve this problem.
• You have your baud rate too high. Try dropping it down to 19200bps for a 14400bps modem, or 38400bps for a 28800bps modem.
• If you are using windows 3.1x, and have a 16550 com (serial) port, maybe your settings in system.ini are not configured properly. Make sure that the system.ini file has the following lines in the [386enh] section. This file is in the c:\windows directory.

  
  COMnFIFO=1
  COMnRXSize=8
  COMnTXSize=0
  MinTimeslice=20
  WinTimeslice=100,50
  COMnBuffer=256

  The "n" in the 1st, 2nd, 3rd, and 6th lines is the number of the COM port your modem is on (so if you're on COM2 it should read COM2FIFO=1). If the lines are there, modify them. If they are not there, add them.