Thank you for the post.
The only way I was able to replicate this behavior was with a custom menu which had "Preferences" added multiple times to the menu set. I suspect this may be the case in the file that triggers this behavior when opened.
In the file with the custom menu, as long as the Tools menu has not been removed, click Tools>Custom Menus and choose the "[Standard FileMaker Menus]" and menus should go back to the default. See screenshot below.TSFalconFileMaker, Inc.
Interesting. Because the menus had always looked pretty standard to me, I had never realised that custom menus were actually on. (I did not do the initial design and implementation of this DB, but I have made some changes to it. However, after changed the custom menus setting back to "[Standard FileMaker Menus]", the multiple "Preferences..." entries were still there. The only observable difference in the FileMaker menu is that the first item changed from "About FileMaker Pro..." in the custom menu version, to "About FileMaker Pro Advanced..." in the standard menu version (shown in this screen shot). You will also note that this menu also has many more "Preferences..." items - seems to be a time-dependent thing. However, I will go into the DB and find where the custom menus are set and turn them off, and I suspect that this might fix the problem, but there would certainly seem to be a bug in the custom menu processing in order for the additional items still to be there when the menus were reverted to standard.
Thank you for the reply.
Looks like the default FileMaker Pro menu set was modified. If you do not need custom menus in this file, deleting the custom menus and custom menu sets from File>Manage>Custom Menus, quitting and reopening the file, will then set everything back to default.
If you need custom menus in the file, you can recreate the menus afterwards.TSFalconFileMaker, Inc.