Background:  Was attempting a flight plan from 96WA (Jim & Julie's) to KNUW then 57WA.  The flight plan would not load in MSFS.  No error just nothing would happen.  I messed around with it going back and forth using MSFS to build the flight plan and it turns out the special characters in the airport name need to be modified.

Specifically the ampersand and apostrophe

Plan-G :
<DepartureName>Jim & Julie's</DepartureName>

MSFS :
<Descr>Jim &amp; Julie&apos;s to Kent Farms</Descr>
<DepartureName>Jim &amp; Julie&apos;s</DepartureName>
<ATCWaypoint id="Jim &amp; Julie&apos;s">

Once I modified any of the special characters with the &amp; and &apos;  the file loaded correctly.

Examples attached.

https://en.wikipedia.org/wiki/List_of_XML_and_HTML_character_entity_references#Predefined_entities_in_XML