When you need to delete large numbers of files you can use this simple batch file command to discard an unlimited number of files:
del C:\foofolder3\test1.txt del C:\foofolder3\test2.txt del C:\foofolder3\test3.txt del C:\foofolder3\test4.txt
Just enter 'del' in front of the file paths for the file you need to delete in a text file. Save it. Change the extension to '.bat', and double-click. It will run and quickly delete all of the files you have specified.