New import won't play

All new songs imported from ripped CD will not play. The songs will play in Window's media player but not with Mp3tag. All other songs will play when right mouse clicked and Play option clicked, but not the most recently imported songs. I have closed and refreshed mp3tag, but still this problem persists.
I am new to this forum and I am not a programmer, so I only have computer literacy skills of average user, so computer lingo used in your reply needs to reflect this status please.
Is there too many songs in my library, is it over full, (currently just under 3000 songs in library)? It seems strange that all other songs are able to be tagged as are these new imports, but the previous collections of songs all played from the mp3tag app, the most recent ones won't. They start playing in the Groove App but after 1 to 2 seconds of play the song cuts out. These same songs play on other apps on my computer, like Window's Media Player. The tagging works.

MP3tag is not a player.
It usually calls the default player for the repective file type as set for your local environment.
So I would check there what is wrong.
You can also add a special program that is executed when you double-click a file:
Go to Extras>Tools>Tools
Add a new tool like WMP and the parameters you need to open the current file.
see the FAQs for more details: /t/966/1
Activate "Start special program on double-click"
Select the name of the just added new tool
Click OK.

But as you say that the files (you do not tell us which type) have problems with other programs, it might be worth a try to check for corruptions.
For mp3 files good utilities would be foobar and mp3diags.