Dear Dr. McLaren,
I have encountered some errors when conducted ppi analysis.
My data was ER-design, 6 runs, 5 conditions. I have conducted first level analysis and got SPM.mat (with 32 contrasts).
The error was reported as: 
%%%%%%%%%%%%%%%%%%%%%%%%%%%
Parameters used:
Processing subject: Sub29
VOI file : G:\Yan.X Projects\4_fMRI_Self_Suppression\RSA_ONE_SUB_20170622\Try_gPPI\GLM\Sub29_Sub29_R_hipp_23_-35_-2_radius_10mm_roi_cond_psycond_PPI_structure__psycond_PPI_structure_ 16-Nov-2017.mat
Output file will be: Sub29_Sub29_Sub29_R_hipp_23_-35_-2_radius_10mm_roi_cond_psycond_PPI_structure__psycond_PPI_structure__session#_cond_PPI_regressors.txt
Contrast : No adjustment
Analysis : Psychophysiological Interactions
Extraction : eigenvariate
Tasks : _1_Baseline_Retrieval Negative_Retrieval Positive _Suppressive Negative_Suppressive Positive
Method : Condition Specific
Program will exit. mat-file is not formatted correctly.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
I am not sure which mistakes I made, may be I did 32 contrasts in first level? or I just did use the same name in the contrast matrix?
Could you please do me a favor and look at the following code?
%%%%%%%%%%%%%%%%%%%%%%%%%%%
P.Contrasts(1).left = {'Retrieval Negative'};
P.Contrasts(1).right = {'Retrieval Positive'};
P.Contrasts(1).name = 'Retrieval Negative-Retrieval Positive';
P.Contrasts(1).STAT='T';
P.Contrasts(1).Weighted=0;
P.Contrasts(1).MinEvents=5; 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Hi,

Your VOI mat-file is not formatted correctly for the current version of gPPI.

What does your VOI mat-file contain for variables?

Best,
Donald

Thanks for your so quick reply,now I changed the VOI name as".nii" format, it works!
But I encountered another question, reported as follow:
%%%%%%%%%%%%%%%%%%%%%%%%%
VOI has 925 voxels in 2x2x2 space

VOI has 272 voxels in 3x3x3 space. This is in the the same space as the input data and functional mask.
Retrieval Positive does not exist. Program will exit
%%%%%%%%%%%%%%%%%%%%%%%%%

The condition"Retrieval Positive" exited indeed, I am confused about that.
Could you please help me again!
Thanks in advance!!
Best,
Xinyuan

sorry, I just checked the code, I typed a space after the condition name.
Thank a lot for your help!!
XY

But I have another question, in my SPM.mat, there are 12 beta images, from beta_0006 to beta_0012 was head movement regressors and constant, and each condition had its unique name. The error was reported as: 
%%%%%%%%%%%%%%%%
estimate_PPI.m
Estimation Failed
Warning: Missing conditions!!! Invalid Contrast
Invalid Contrast
Warning: Missing conditions!!! Invalid Contrast
Invalid Contrast
Warning: Missing conditions!!! Invalid Contrast
Invalid Contrast
PPI Contrasts were not estimated for some reason.
%%%%%%%%%%%%%%%%
Dose the SPM.mat for estimating cannot contain the head movement regressor?

Best,
Xinyuan

What was the P.WB setting?

There should be no issue with including motion parameters in the gPPI model.

Best,
Donald