When I run cmd in Windows 7 (by typing 'cmd' in Windows Run), the following error shows:

'-p' is not recognized as an internal or external command, operable program or batch file.
I have tried checking PATH in environment variables.
Running echo %PATH% gives me the following:
C:\Windows\System32;C:\Windows;C:\Windows\System32\WindowsPowerShell\v1.0;C:\xampp\php;
I have checked all the directories being pointed to by PATH. Everything seems to be in place. What I can not understand is where '-p' is being called. I'm thinking that it has something to do with cmd since it only comes out when I call cmd and not when I run ipconfig or ping, for example.
R, which should have been in his path but was not, due to that mistake. This case is of the command processor (cmd) itself raising the error on start - and the start was successful. Still, the problem that caused it might be the same; I won't discount that...