This warning is not usually a serious issue that is most likely to harm the system during the course of finding what must have been the cause of the error warning message. In the time of scrutinizing it there is every palpable evidence pointing to 'Virus Protection'. Take note that there is no need to worry much about having virus or malicious software which could be harmful to the desktop present or residing in the heart of the operating system.
First and foremost, it wise to take to frugal check in the advanced feature of your BIOS setup, that is usually the cause for the particular culprit that could have trigger the warning message. Check properly to make sure the Virus Protection is not enabled because this can be a factor.
(a) When the Advanced BIOS setup virus protection feature is not the cause.
If there has been over partitioned and reformatted of the HD over and over again and still plagued with receiving such message when the computer tries to do the installation and ends up with ''Caldera DOS at A prompt'' the following steps are meant to help out with the issue.
Step 1: Try to use a new Window XP or system installation disk that is different from the former one used to do your installation(the version of Window installation disk is necessary ). The installation disk must be bootable to continue with the setup process.
Step 2: Make sure there are no cracks or scratches on the installation DVD/CD.
Step 3: Clean the installation disk with solvent solution or with water added to a soft tissue or cloth.
Step 4: Insert the installation disk into the system and try to do the installation.
2. After using a new installation disk the computer is still repeating the same warning message
This can happen sometimes not often--- as I found out in some systems which the Virus protection can auto-internally be enabled while still disabled at the BIOS setup(I observed this in some computers which BIOS have been flashed for upgrade) .
Step 1: Go back to BIOS setup and enable the virus protection feature
Step 2: The system will immediately ask 'if you want to scan your hard disk, if you aren`t the person who made this change'..
Step 3: Press ENTER without making any option and the system will boot up and continue with installation.
Step 4: After completing the installation go back into the BIOS and disable the 'Virus protection option' .