User's Manual

194 APPENDIX D: TROUBLESHOOTING
Device is in a reboot loop Software fault Download and install a working or previous software
version from the console
No connection and the port
LED is off
Incorrect ethernet cable,
e.g., crossed rather than
straight cable, or vice
versa, split pair (incorrect
twisting of pairs)
Fiber optical cable
connection is reversed
Bad cable
Wrong cable type
Check pinout and replace if necessary
Change if necessary. Check Rx and Tx on fiber optic cable
Replace with a tested cable
Verify that all 10 Mbps connections use a Cat 5 cable
Check the port LED or zoom screen in the NMS
application, and change setting if necessary
Lost Password Contact 3Com
Table 12 Troubleshooting Solutions (continued)
Problems Possible Cause Solution