Java exception when trying to import image sequence

[asteroidguy]

Running AIJ 5.0.3.02 for a while, the Import -> Image Sequence function suddenly stopped working. It throws the following exception:

AIJ 5.0.3.02; ImageJ 1.53k; Java 17.0.1 [64-bit]; Windows 10 10.0; 11MB of 3000MB (<1%)
 
java.lang.NullPointerException
        at java.base/java.io.File.<init>(Unknown Source)
        at ij.plugin.FolderOpener.getFileCount(FolderOpener.java:799)
        at ij.plugin.FolderOpener.showDialog(FolderOpener.java:579)
        at ij.plugin.FolderOpener.run(FolderOpener.java:151)
        at ij.IJ.runPlugIn(IJ.java:208)
        at ij.Executer.runCommand(Executer.java:151)
        at ij.Executer.run(Executer.java:69)
        at java.base/java.lang.Thread.run(Unknown Source)

I was going through numerous directories in a AIJ instance that was already running for a long time when that error suddenly happened. I am unable to clear the error - neither restarting AIJ nor starting with a fresh setup of AIJ5 do help. I am afraid something must have upset the file import dialog window. How can I recover from this error?

EDIT: Edit -> Options -> Reset... provided the remedy, but not sure how I managed to throw it off in the first place...

[karenacollins]

I think you mean that files that are known to have opened previously will no longer open. If that is correct and you have already re-installed AIJ v5, then the only left-over file is the AIJ_prefs.txt file, which is retained across installations. Let's try resetting that file to defaults in case something is corrupt in the file.

If you are instead trying to open a new file that you have not opened previously, we'll need you upload a sample for us to use for testing.

Now back to resetting your prefs defaults.

Unfortunately having to reset your default prefs file will mean you'll have to set up plot settings, etc. again the way you like them. However, as part of the default restoration, AIJ will save the current settings in a backup file. If it turns out that the restoration of default prefs does not solve your problem, you can restore the original prefs from the backup.

Go to Multi-Aperture Main > File > Restore all default AIJ preferences. Follow directions.

Then close and re-open AIJ. Now try to open you image sequence again.

If this fixes your problem, please post the prefs backup file that you created so that we can try to understand what instigated the problem.

By the way, if you have changed any of the files in the AIJ installation directories, you may want to start from another AIJ v5 install first.

Karen

[karenacollins]

If you get into this state again, please send us a backup of your AIJ_prefs.txt file (go to Multi-plot_Main > File > Save AIJ Prefs to backup) and an example of a fits image  that causes the problem. We'd like to track this down and solve it when it shows up again.

Karen