Try copying the php extension dll from the \xampp\php\ext folder to the \xampp\apache\bin folder and then try again.
Move the aspell dll back to the system32 folder as outlined above.
This has been found to be a system path environment variable issue that may be caused by using the installer exe version as opposed to using the zip or 7zip archive version and the above has solved it for some instances of the system not being able to find an extension dll.
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The installer will be replaced in the next XAMPP release that will hopefully eliminate some of these issues).
BTW you may have more issues in future with some XAMPP components ported from Linux by installing XAMPP to a folder with a space in the name (they can't handle spaces in file or folder names).
The recommended location for XAMPP as defined in the readme_en.txt file is to the root of a drive or partition so you end up with, for example, C:\xampp.
Let me know back please if copying the extension dll allows you to move on.
Thanks and good luck.