There are a number of viruses/trojans that can cause this. This link has manual removal instructions for ONE of them plus the is a tool available from TrendMicro at the bottom of the page.
i have an error pop up when i turn on my computer. it says: "WININIT.EXE:MISSING\UNABLE TO LOAD PRESSA NY KEY TO CONTINUE." and before my desktop loads another error comes up stating: "WINDOWS CANNOT FIND '\P' YOU MAY HAVE TYPED THE NAME INCORRECTLY IN THE RUN DIALOG OR ANOTHER OPEN PROGRAM CANNOT FIND A SYSTEM FILE. TO SEARCH FOR A FILE, CLICK THE START BUTTON, AND THEN CLICK SEARCH." i have always had mcafee antivirus since i purchased the computer. i also have a spyware blocker and firewall through AOL. i recently purchased a norton antivirus and firewall which will not download into my computer. i was told those errors are more than likely a virus so i figured mcafee was not doing a good job. i scanned my computer using housecall and it found nothing i have also used a number of other online free scans and nothing was found on any of the scans. do you have any ideas on how to get this error fixed?