How to Fix Windows 10 Upgrade Compare Exchange128 Error Message
Compare Exchange128 error – What is it
Some Windows 7 and Windows 8.1 users reported experiencing a Compare Exchange128 error when trying to upgrade to Windows 10. The error reads, “You can’t install Windows 10 because your processor doesn’t support CompareExchange128”. In order to upgrade to Windows 10 (64-bit), the CMPXCHG16B instruction must be present. If you receive this error, this mostly means that your CPU doesn’t have the CMPXCHG16B instruction.
The CompareExchange128 error normally occurs due to two possible reasons:
- CPU lacks CMPXCHG16b Instruction
- Old & Outdated BIOS – Even if your CPU has the CMPXCHG16b instruction, the CompareExchange128 issue can still occur if you have an older BIOS.
Further Information and Manual Repair
One main requirement to upgrade to Windows 10 is for your CPU to have the CMPXCHG16b instruction. You also need the right BIOS version to guarantee a smooth installation. See below on how to manually fix this issue.
NOTE: If you don’t feel confident using the manual methods listed below, it’s highly advisable to get help from an expert technician. If you don’t know someone, you can also use an automated tool to fix this.
Before performing any fixes, try to determine first if the cause of the error is due to your CPU lacking the CMPXCHG16b instruction. You can use a CPU Info tool that provides complete details about your processor, memory, and motherboard. If you’re looking for more in-depth information, you might also try command-line utilities. But, the safest and easiest way to check this is by simply searching online. Try using the search query: <CPU Model> CMPXCHG16b
Method 1 – Update your BIOS
This method will download the latest BIOS from your motherboard’s manufacturer. This makes sure your CPU has the CMPXCHG16b instruction needed to complete the Windows 10 64-bit installation. To update your computer’s BIOS, complete the following steps:
- Determine first the current BIOS you have on your computer. Open System Information Windows app and type msinfo32 in the search bar. The BIOS version will appear under the processor speed. Record it somewhere.
- Go to the support page of your motherboard’s manufacturer. Find if there’s any update on the BIOS that you’re currently using. If you find one, download the BIOS update file available. Make sure that you’re looking into the right model and you download all the necessary documentation. Otherwise, the BIOS update might not work.
- Update your BIOS. Most BIOS update steps are straightforward. Just make sure to follow the steps provided.
Method 2 – Install Windows 10 32-bit version
If updating the BIOS doesn’t work, what you can do is install a 32-bit version of Windows 10 instead of the 64-bit version. Here’s how to do this:
- Download and install the 32-bit version of Windows you currently have. If you have a Windows 7 64-bit version, get the 32-bit version of Windows 7. The same goes for Windows 8.1. When you do this, you might want to back up your files first. Remember that installing the 32-bit version works like other installations, and could delete some of your files.
- After installing the 32-bit version, go to Updates and install all the necessary updates. This includes upgrading to Windows 10 if you’re asked to.
- When you installed the Windows 10 upgrade, you’ll now have the Windows 10, 32-bit version installed. This will be the version activated on Microsoft servers. Despite this, the activated version stored is only applicable to your computer’s hardware, not the version of Windows 10.
- Download Windows 10, 64-bit version.
- Prepare an empty DVD or USB flash drive. Use Creation Media software then click the Create Installation Media for Another PC option.
- Install the 64-bit Windows 10 version you downloaded from Step 4. Make sure not to put anything when you’re asked to input the serial number.
- Once the installation is complete, you’ll have the 64-bit version of Windows 10.
Method 3 – Buy a new processor/motherboard
If the above two methods don’t work, there’s a great chance that this error occurs because of an outdated processor/motherboard. Your next possible solution is to buy an updated model that’s fully compatible with 64-bit Windows 10.
Method 4 – Download an automated tool
If all else fails, you might want to consider using this powerful automated tool to quickly fix the problem and any other computer-related issues.