No peaks found

Threshold setting is too high

Reduce the threshold setting.

Emission current was set to 0

Return the emission current to its former value or to the default value.

Electron multiplier voltage is too low

Increase the electron multiplier voltage. If the electron multiplier voltage is at or near its limit of 3000 V, you may need to replace the electron multiplier horn. See the MSD maintenance documentation for instructions for replacing the electron multiplier horn.

AMU gain or offset too high

Retune the MSD or reduce the amu gain and offset.