No, you can't. It quite clearly states in the initial Expander GUI that you can expand volumes formatted with NTFS, and you probably got a warning message when you pressed ahead with your exFAT volume that the file table wouldn't be updated (though the implications of this are not spelt out, that the extra space will therefore be 'invisible' to Windows).
Last edit: Adrian Kentleton 2018-08-08
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Hello!
I just used VeraCrypt Expander and it's works for a long time.
Now I see this.

It's normal? How many time I need to wait?
Do you use a custom PIM? If yes, how long do you normally wait for the volume to mount before you expanded the volume?
It will be double the time to write new primary and embedded backup headers.
Thank you for your answer. Everything fine. It takes about 10 hours =)
But I have new question. In "My computer" in my Volume I have only 500 Gb but in VeraCrypt 750 Gb. So can I use more than 500 GB?
Last edit: Art 2018-08-08
No, you can't. It quite clearly states in the initial Expander GUI that you can expand volumes formatted with NTFS, and you probably got a warning message when you pressed ahead with your exFAT volume that the file table wouldn't be updated (though the implications of this are not spelt out, that the extra space will therefore be 'invisible' to Windows).
Last edit: Adrian Kentleton 2018-08-08
So if I can't use extra space why Expander allow do this? They need simply prohibit this function.
PS Yes I saw warning message before I clicked. But I thought that Windows will not see the extra spaxe, but I can use it.