You might need to consider using a https://learn.microsoft.com/en-us/do...m.timers.timer timer - I have a feeling a minimized form doesn't receive any Windows Messages and therefore a WinForms Timer isn't going to update... Although I could be completely wrong about this.

Then again the problem could be elsewhere, for starters with code like
Code:
   Dim Todayt As Date = Date.Now.ToString("MM/d/yyyy")
You are converting a date, to a string, and back to a date and hoping that the conversion works - if you are after the date but not the time then this should work
Code:
       Dim today As Date = Date.Today
I would also avoid DateDiff in VB.Net as this is just a hold over from VB6 and earlier, you can simply subtract one date from another to figure out how far apart they are.