I have installed build 10049 today. Why have I got a Windows.old directory dated 1st April 2015?
The Windows directory is dated 31st March 2015 which makes sense.
Is the clock on your pc correct?
Yes, I have not touched it.
To cause you confusion, and it worked. Do a disk cleanup and deleted it, no more problem. . .
Two directory packages on the same machine, old or new, probably causes some kind of conflict in the file system.
Windows.old is caused when you upgrade from one version of Windows to the next. It's perfectly normal. This mainly happens if you upgrade from within windows rather than doing a clean formatted install.
To clear those folders run cleanmgr.exe, click on the clean up system files button then there should be an entry to delete old install files. This will remove windows.old and a couple of other folders created during the upgrade.
You can't delete these manually you have to use this program.
WARNING: There may be a possibility of some settings loss but its usually minor.
I thought the date might be significant! So far this new build is vastly better than build 10041 which appeared to dislike my graphics card.
April fool?
Maybe you have a time machine. Check the settings on your flux capacitor.
Yep lots of folks like to play the fools game. Software folks have been known to do a little bit of that.