Thank you for the suggestion 5618, but unfortunately that did not resolve the issue. The same problem occurred, even though I installed the program in a different location.

I tried to delete the executable from the application folder, and replace it with the new one, but it would not delete. It seems that access is denied, even though the file is not write protected, or in use, as far as I know. As I try to delete the executable, or run the executable, my virus protection alerts me to a file named "Client-IRC.Win32.mIRC", saying that the file is potential riskware/malware.

I am beginning to suspect that my problem is linked to my virus protection, as I receive that message on a regular basis, every time I try to run mIRC, even though I tell the program to take no action. Perhaps my virus protection is impeding the installation in some way. Would mIRC be capable of running if I delete the above file? Also, would you happen to know exactly what it is that this file does that would make it be detected as a risk?

EDIT: I should mention, incase it is of any significance, that the mIRC executable does not resemble the usual mIRC insignia. I don't know the suitable name for this type of icon, but I assume it is Windows default exe. icon when it is unaware of what program it is.

Thank you again for your helps guys.