Path: utzoo!attcan!uunet!sbi!zeus!cf_su10!cf_su20!nee From: nee@cf_su20.Sbi.Com (Robert Nee) Newsgroups: comp.sys.ibm.pc.misc Subject: Re: Disabling DOS internal commands ? Message-ID: <158@cf_su20.cf_su10.Sbi.COM> Date: 24 Jan 91 14:44:07 GMT References: <1991Jan23.120842.3032@newcastle.ac.uk> Sender: news@cf_su10.Sbi.COM Reply-To: nee@cf_su20.Salomon.Com (Robert Nee) Organization: Salomon Brothers, NY Lines: 23 > Is there any way of disabling DOS internal commands ? Alternatively > can DOS be persuaded to execute a program of the same name as a DOS > internal command without explicitly specifying a path ? The easiest way to disable internal commands is to alter a second copy of COMMAND.COM with something like Norton. Search for the text of the command you wish to alter. Notice that the commands are listed on all uppercase. Simply changing the command to lowercase will disable it. This method works because DOS converts you command line to uppercase before proccessing it. It then performs a case-sensitive compare with all of the internal commands. Since "COPY" won't match "copy" the command is effectively disabled. In addition changing the command to lower case will allow you to easily find where the change was made in case you wish to alter it later. If you rename VCOPY to COPY users will really be executing a virus free copy. Remember, never try to patch your only copy of COMMAND.COM. Always attempt patches on a backup copy. Robert F. Nee