Download and install a noise-removal plugin. Visit a website such as KVR Audio, VST 4 Free or VST Planet and search for a noise-distortion plugin from its database. Some, if not all, plugins are available for free at time of publication from these sites. Copy the plugin's ".dll" file to your recording software's "VST" folder by copying-and-pasting it into the folder location on your hard drive.
Open your digital-audio workstation software, such as Ableton Live, Cubase or FL Studio, and load the project containing the guitar recording with distortion on it. Double-click the desktop icon to start the program, click "File," "Open," and then select the guitar project from the list on the pop-up screen.
Add an instance of a noise-removal plugin to your guitar track. Cubase users: Click the track with your mouse, click "Sends," select "Post Fade Send," click the dark area below and then select the noise-removal plugin from the list. Ableton Live users: Click the second button underneath the arrow at the top-left of your screen, then click-and-drag the plugin onto your guitar track. FL Studio users: Click "Mixer," select your guitar track, click the first slot on the right side of the pop-up screen, then select the plugin from the list that appears.
Adjust the noise-removal plugin's settings to remove the unwanted distortion. Increase or reduce the "Threshold" and "Sensitivity" knobs or sliders with your mouse to fine-tune the effect processing over your guitar's recording. Mute and unmute the effect within your program's mixer to get an idea of how the original recording compares to the one with the effect
Save the project. Click "File," Save As" and enter a name for the project that identifies it as the modified version. A name such as "GuitarTrack2NoDistortion" will make the file easier to recall at a later point in the engineering process.