… I tried everything in correcting this but nothing seems to work …

If you have “tried everything”, and “nothing seems to work”, then you should open a support case with MakeMusic, and report the bug.

However, are you sure that you have “tried everything”?

Please specify the steps you've already taken, so that we can rule out things.

Without knowing more about the Finale document we can only guess.

Here is a “shot in the dark”:

Go to Document menu > Page Format > Parts…

and edit the settings so that they are, as you need them.

The settings only affect new systems/pages.

Already existing systems/pages are not affected.

To update already existing systems/pages in the part:

View the part (Document menu > Edit Part > …)

Switch to the Page Layout Tool.

Page Layout menu > Redefine Pages > …

What version of Finale? If 25, what build?

What program created the .xml file?

Thanks Peter and Mike for replying!
@Peter: My 'I tried everything' was obviously used as a matter of speech. Anyway, I already did tried the solutions you suggested, like Redefining Pages. Result: nothing happened. I then started the process all over, exported and imported a new xml file and tried again. This time Redefining Pages option worked and the generated part looks ok. So probably something went wrong during export/import of the xml file.
@Mike: I use Finale 25.4.1.152 which is the lastest update as far as I know and the xml was created by Capella 7.1

Ok, you have the latest version of MusicXML. Good. Glad you were able to fix this the second time around. 

Have you gone back to the software that produced it and looked to see if it had an ability to set the number of measures per line. I do some work with XML but I am just starting out. In my case I had written a keyboard part for a song I am recording and decided to write keys to play along with the guitars. So I entered the lead part in my daw as I played along with the lead part and captured it that way... so I could embed things like pitch bending anyways when I went to export via XML it required me to enter the number of measures per line. I am wondering if that may be the problem. Maybe it should be set to export at 3 or 4 measures per line. But then again that may have nothing to do with what you are doing. It was just a thought.

@Bob Sherwin: Thanks for your reply. No, the software that generated the XML (Capella 7.1) dit not have the ability to set the number of measures per line. Even without this ability importing the xml file worked the second time I tried without major problems.