Problem installing msi-based packages as it shows "access denied" message

[catalyst]

My operating system is windows XP Pro. For the past few days I am noticing that whenever I try to install any programs with extension as .msi it shows "access denied". The problem does not occur with .exe based program extensions. The same thing happened sometimes back with .txt files and .ini files. I solved it by creating a program association with notepad and the problem stopped.

[Amargusain]

dude, You sure that you're logged on to an account w/ adequate permissions.
further, if this is something thats hapng w/ all .msi files .. try repairing/removin the Microsoft Installer service.

FYI .. its available as a dld thru Windows Update.

[catalyst]

yes I have all administrator rights and privileges. The microsoft installer service cannot be reinstalled on xp os.