Apple MD094LL/A Manuale Utente

iMac (27-inch, Mid 2010) Symptom Charts — Communications 

 2010-09-09

4.  Check for speed and duplex 

issues on network. Open 

System Preference > Network; 

click the Advanced button, 

then the Ethernet tab. Verify if 

the speed and duplex reported 

are what is expected.

Yes

Go to step 5.

No

Change speed and duplex 

settings. See article 

. Go to step 6.

5.  Check for MTU (Maximum 

Transmission Unit) issues. See 

. 

Verify if changing MTU settings 

on computer resolves issue. 

Yes

Go to step 6.

No

Ethernet controller damaged. 

Replace logic board.

6.  If changing speed, duplex 

or MTU settings allows 

connectivity, check with a 

known-good, same-model 

computer. Verify if known-good 

computer produces the same 

results.

Yes

Check with ISP or Network 

Administrator concerning 

speed, duplex & MTU settings.

No

Verify with known good OS. 

If issue persists, replace logic 

board.

Pair
•  Can’t get system to recognize a 

Bluetooth keyboard, mouse or 
trackpad

1.  Check computer with a known-good Bluetooth 

input device to test computer side.

2.  Test Bluetooth device side with a known-good 

computer, with up-to-date Mac OS 10.6.x with 

installed Bluetooth device driver. 

3.  Ensure that device is being used within 30-foot 

range for Bluetooth devices.

4.  See