I was recording - something I've done many times before - but the computer is brand new (L540 ThinkPad) through the USB port from a synthesizer with a Audio to USB interface, and the internal microphone on the ThinkPad was recording room noises along with the synth, so I went to the control panel, clicked Sound, went to the Recording Tab and removed the RealTek internal microphone from the system.
Is there any way for me to get it back?
Unless a program has been uninstalled via the Control Panel, it remains in the system.
In this situation, it is likely that the program itself has been disabled, rather than deleted.
Proceed with the following steps to reactivate the microphone:
1. Right click on the microphone icon to check if you have a "Hide disabled devices" option. If it has been hidden, enable or activate it.
2. Check Device Manager in Control Panel (Control Panel>> Device Manager). Check if the microphone is there and enable it as per the steps in Method 1. If there is an unknown audio device instead, you may have to reinstall your audio driver from http://support.lenovo.com/
If you have neither, click on Add New Hardware Wizard (hdwwiz.exe).