TP-Link archer t2u User Manual page 6

Chapter 1
You can check the adapter's working status by following the LED Explanation table.
Status
The driver has not been installed.
Off
The adapter's radio has been disabled.
Flashing Slowly The driver has been installed but no data is being transmitted or received.
Flashing Quickly Data is being transmitted or received.
Tips:
If the LED is off, try these troubleshooting tips:
1. Remove and reinsert the adapter.
2. Insert the adapter in a different USB port on your computer if one is available.
3. For Windows users, check the Windows device manager to see if the adapter is recognized and enabled. Reinstall
the adapter software, if necessary.
Get to Know About Your Adapter
Indication
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