Auto tune fails: Cannot perform coarse Mass Calibration?

I have added a tag to increase visibility. Failing tunes can be caused by many situations.

1. Age of tune solution

2. Charging in source or ion path. Clean or replace ion capillary.

3. Corrupt tune file try replacing tune file with a known good tune file.

Here are some things to start with.

Mitch

Is there a tell-tale sign that it is the tune solution? Can tune solution just drop in overall abundance?

Hiamalicule ,

I always recommend to customer to look at the  tuning solution in positive first (if you have a TQ, go in MS2 scan) as you will see if you have any contamination. A good tell-tale of a degraded tuning solution is the presence of unknow peaks, low abondance's on tuning peaks, etc.

When looking at the tuning peaks, you also want to make sure that you do not have other masses interfering with your compounds of interests. Mass 118 and 322 are more susceptible to have contamination close by.

I hope this helps.

Regards,