Masshunter Quantitative Analysis - Error "Calibration STD path mismatch between target and ISTD"

Question

I am still learning Masshunter Quantitative Analysis for LC/TQ and I have version 12.1 build 12.1.938.3. 
 
 I have run into this error multiple times and the only way I've gotten out of it so far is to close the software and start over. This is very frustrating as I go into edit a method and assign Surrogates to ISTD and then Targets to Surrogates. Once this is done, I go to "Exit" and try to analyze or quantitate the batch. I then get this error: Calibration STD path mismatch between target and ISTD. 
 I have not found a way to save what I've done and close the software to try and get out of this error. I'm not finding any information online on how to fix this error. 
 I would love to know how to fix it without losing all of my work and not creating 15,000 copies of a method since I'm not done with creating the quant method. A lot of times they open as "read only" and I also have to start over. 
 How do I fix this error? Do I just need to move the ISTD and cal.d files to a different folder? 
 When I'm in Quant and create a new batch, I then go to "Open and Apply from Existing Batch". 
 I'm sure I'm missing something easy but getting very frustrated here.....

howard_sanford · Answer

Hello voldiver , 
 I apologize for the delayed response. 
 I'm not aware of specific issues with this in the 12.x versions, but generally, as Googlenation mentions, this error means that there is a mismatch between the cal. path/file specified for an ISTD and its associated target. One way this can occur is if you have an ISTD that you don't use for all methods, but you keep the compound present. If there is an ISTD that is not used, you will receive a warning on exiting the method, and quant will not run analysis on that compound, leaving its Cal. Path as it was the last time it was used as an ISTD. If in a later batch you then attempt to 'enable' this ISTD, this error will occur since the old cal path is stuck for this compound. 
 In addition to Googlenation suggestion, you can also temporarily set the ISTD to be a target. Then quant will analyze the compound and update the cal. path. After this you can set it back to be an ISTD and everything should work.