Blank page with an "M" on the upper left hand corner

I'm trying to add a new product, and I'm getting a big fat blank page with an "M" on the very top left hand corner.

This also happened with another action I was doing. I was editing the paypal section, and when I clicked "save", the same blank page with the "m" came up, but it DID take the changes.

I'm not sure what's going on, but now, I really cannot add new products.

Anyone seen this before?

Thank you,

I'm working with 1.3.7

https://www.extremedigiscraps.com/Store

Thank you,
Addie

Hey addie, I do not know if this will help but there's an article in the tutorials section, regarding blank pages. Look it over and see if it helps.https://www.zen-cart.com/tutorials/index.php?article=82

That M is probably being output prematurely and causing "headers already sent" or "encapsulated string" errors that are being suppressed. The debug facility referenced on the FAQ page to which EBTown has directed you will help you to find out what those errors are, and hopefully the file and line number that is causing them.