$mircdir $+ Tempinvite.txt

You don't actually need the $+

$mircdirTempinvite.txt

will get the job done. You should proofread your code before submitting. I mean, we all make mistakes at one point or another. It's best we make sure our codes appear to be as perfect as possible.

Now, some people may comment on your snippet with a somewhat "harsh" tone to pinpoint the fallacy of your script, just ignore that and take that as an incentive for improvement.