Hi Ya,
The problem here is that the 1242 you received is a "Lightweight" model as shown by this part number from your info cisco AIR-LAP1242AG-E-K9. This model is made to operate with the Wireless Lan Controller type Unified deployment. You can convert it to Autonomous or Standalone mode using this method;
You will need to load an IOS on the 1242 before you get the ap> prompt.
Using a TFTP Server to Return to a Previous Release
Follow these steps to revert from LWAPP mode to autonomous mode by loading a Cisco IOS release using a TFTP server:
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Step 1 The static IP address of the PC on which your TFTP server software runs should be between 10.0.0.2 and 10.0.0.30.
Step 2 Make sure that the PC contains the access point image file (such as c1200-k9w7-tar.122-15.JA.tar for a 1200 series access point) in the TFTP server folder and that the TFTP server is activated.
Step 3 On the PC where the TFTP server is located, perform these steps:
a. Disable any software firewall products, such as Windows firewall, ZoneAlarm firewall, McAffee firewall, or others.
b. Ensure all Windows files are visible. From Windows Explorer, click Tools > Folder Options > View > Show hidden files and folders.
Step 4 Rename the access point image file in the TFTP server folder to c1200-k9w7-tar.default for a 1200 series access point, c1130-k9w7-tar.default for an 1130 series access point, and c1240-k9w7-tar.default for a 1240 series access point.
Step 5 Connect the PC to the access point using a Category 5 (CAT5) Ethernet cable.
Step 6 Disconnect power from the access point.
Step 7 Press and hold MODE while you reconnect power to the access point.
Step 8 Hold the MODE button until the status LED turns red (approximately 20 to 30 seconds) and then release.
Step 9 Wait until the access point reboots, as indicated by all LEDs turning green followed by the Status LED blinking green.
Step 10 After the access point reboots, reconfigure it using the GUI or the CLI.
http://www.cisco.com/en/US/docs/wireless/access_point/conversion/lwapp/upgrade/guide/lwapnote.html#wp161272
Hope this helps!
Rob
