1/ The most common problem comes from an issue in which the macro attempts to write data files to the hard drive but does not have access to that area. Make sure that you have permission to write to the location specified on the CD command, the folder specified does indeed exist, and that that location is exactly correct.

2/ Another common problem is that SPSS data files are already open on your computer, which may occur because of an earlier error in attempting to run the macro. And because open files cannot be written to, making sure that all of the data files (except perhaps the original data set) are closed should solve this problem. Best strategy usually seems to be saving your syntax file, exiting out of SPSS, and rerunning the model.

3/ You may get most of the results but the significance tests for the simple slopes is missing. This is most likely do to the issue described in 2/ above.

4/ Make sure that the location of the macro given on the INCLUDE command is exactly correct and that the simple1.sps is there. Also, there is no need to have the macro file open SPSS when running the analysis, so be sure that the macro is closed.

5/ There is no need to alter the information in the macro. After downloading it, just save it to a known location on your hard drive.

6/ Is may be problematic to use a flash drive, network drive, or online location for the CD or INCLUDE locations. Doing so is likely to lead to problems.

7/ Make sure you have renamed the appropriate variables to x (predictor on x axis), z (moderator, plotted on separate lines), and y (outcome variable) and that there are no unusual problems with any of these variables (outliers, string variables, constant values). The variables x, z, and y should not be specified on the SIMPLE1 line—they are assumed by default. Only add any desired covariates there and leave the list blank otherwise, such as SIMPLE1 VARS=.

8/ The macro usually works on SPSS for Mac but there are sometimes extra protections to hard drive regions and allowing software to save files to the hard drive. Some users have reported problems with security updates associated with this issue. Check the latest reports of security update problems from Apple. The CD and INCLUDE locations for Mac do not include a letter drive and should typically look like the following: /Users/yourusername/spssfiles/

9/ If none of the above suggestions work, please email me at newsomj@pdx.edu and send me your syntax and output files and I will try to help.