G'day Aaron,
Are you trying to use the Report Builder tool?
Assuming that you are, the dialog has an output file name field. Potentailly, you've used that field before and something has gone amiss with the RSC file that stores the dialog settings.
Try going to this folder:
C:\Users\<your user name>\AppData\Local\Bentley\MicroStation\8.11\fahTqL75JZj2g2gpxRJnFQ\GEOPAK
And delete the RSC file "gdrept.rsc"
With a bit of luck, that will clear the dialog and allow you into it.
HTHs