Question: My full version of Windows 98 Second Edition will not install over Windows 95. It tells me I have a previously installed operating system and I have to quit. What should I do? —Suzanne
Answer: I checked with Microsoft Canada and I am the bearer of bad news. If your version of Windows 98 Second Edition is giving you a message that it cannot install because there is a previous operating system installed, that version of Windows 98 Second Edition is known as an OEM (Original Equipment Manufacturer) copy.
OEM versions are the versions that come when you purchase a new computer. For example, if you were to buy a Compaq computer, and it came with Windows 98 Second Edition installed, that operating system would be known as an OEM version.
Since OEM versions are made for new computers, there is never another OS installed on the system, and it will have no problems installing on a clean hard drive. If you try to install an OEM version of Windows over any system that already has an OS installed, you will be presented with the error that you’ve described.
If you went to a store and purchased this version of Windows 98, they sold you an incorrect version.
Most of the time, stores don’t realize this, and sell the OEM version without question. This is a very common mistake. “Most of the time, both the customer and the store are properly educated after a technician in (Microsoft) Product Support explains the situation to the customer. In turn, the customer explains it to the store,” said a Microsoft Canada spokesperson.
You should take the Windows 98 version back to the store and ask for a retail version of Windows 98 (either the upgrade or full version).
By the way, there is no problem installing a legitimate Windows 98 Second Edition full version over an existing Windows 95 computer.
The only difference between an upgrade version, and the full version, besides the price, is that the upgrade version does a compliance check to make sure a qualifying product exists on the machine, or is in your possession, in order for the installation to proceed.
If you have a full version of Windows 98 Second Edition, it should install over Windows 95 without any problems.
For more reinstall info, please see our Reinstall and Reformat – Windows 95, 98 & ME.