A or an XML report? [duplicate]
Solution 1:
It's "an XML report", because which form of the indefinite article to use is decided by how the next word is pronounced. In this case, it's pronounced:
An ex-emm-ell report
'XML' begins with a vowel sound, 'e', so an is used rather than a.
Solution 2:
"An XML report" - because it is eXeMel - the sound starts with a vowel.