Weird behavior by Windows 7, clock/date field changing

I am furious at not knowing why my date/clock in Windows 7 keep changins its appearance. It is as if the files or settings for Windows change mysteriously back and forth and I don't like it one bit.

The issue pertains to this clock/date shown at the bottom right corner on the screen just beside the system tray.

Sometimes it tells me the clock and no date or anything else is shown.
Some hours later it changes mysteriously to show the clock and the date format I once set, so that I get to see the day of the week, the date in numeral and the month in letters, and finally showing the year.

Something appear to be horribly wrong in Windows and I have no hope fixing it.

Only hope here is if this issue is familiar to other people.

No, it is not like the gui is changing as if it was some kind of mouse over effect.

No point showing a picture.

With the clock alone, it would state:
13:00 (24h clock)

With my earlier customized clock/date it would say for example:
18:00
Friday 09. august 2013 ('Friday' translated to english here)

My settings (short date):
dddd dd. MMMM yyyy

My settings (long date):
dd. MMMM yyyy

I suppose I might have ended up typing in an invalid syntax or something, maybe it is that simple.

Ugh, no, I won't do that. :) Besides, it wouldn't really explain or even fix my issue anyway. Just remove it.

It's been like this for quite some time. Not possible to recall what I might have typed in the first place I am afraid. I have no idea what is going on and there are too many variables to take into account I would say. Pretty obscure stuff I think.

Btw, on a possibly unnrelated note, is there perhaps something wrong with my program installations?

The reason I am asking you guys is that I would expect an entry to show up once or maybe twice if it is for both x32 and x64, in this case I have three versions of something installed. Wouldn't surprise me if that was sort of wrong.

Well, if you look at the image linked, there seem to be three installations of C++ 2008 redistributable v. 9.0.xxx.Might be completely normal, it just looks odd to me.