Can I delete the files System 64, Perflogs,MSI and Mono?

Question

i need more space on my pc, can i delete these folders?

Answer 1

It is generally not recommended to delete system folders like System 64 and Perflogs as they may contain important system files and logs that are necessary for Windows to function properly. Deleting these folders could lead to system instability or loss of functionality.

For MSI files, these are typically associated with Windows Installer packages. Deleting them may prevent you from uninstalling or updating applications that use these installers.

Mono is a framework used for running applications developed with .NET. If you are not using any applications that depend on Mono, you may consider removing it, but ensure that it is not required by any of your installed applications.

To free up space safely, consider using the Disk Cleanup tool or Storage Sense, which can help you identify and remove unnecessary files without risking the stability of your system.

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References:

• Clean Up the WinSxS Folder
• Speed up a Windows 8.1 computer

Answer 2

Hi, good day!

Perflogs is safe to remove, but the others should generally be left alone. If space is still an issue, using Disk Cleanup or uninstalling unused programs is a safer and more effective approach.

Please check the support article below on How to Free up drive space in Windows

https://support.microsoft.com/windows/free-up-drive-space-in-windows-85529ccb-c365-490d-b548-831022bc9b32

If this doesn't work, please try downloading and installing this free tool called TreeSize to identify apps or files that are taking up more of your storage space.

https://www.jam-software.com/treesize_free

Once installed, open the app, wait for the scan to complete then expand the folders

Please check and identify apps or files that are taking up more of your storage space., Select and right click the file you don't need. Click "Delete" to free up space.

I look forward to receiving your update and I'm willing to collaborate with you till we resolve the issue. Do keep me informed by clicking "Add comment" below.

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Answer 3

Welcome Facethefacts,

Thank you for contacting the Microsoft Q&A forum. I’m sorry to hear that you’re experiencing issues due to limited storage on your PC. 

Have you had a chance to review the responses from Q&A Assist and John DeV? If not, you may also want to try a few additional methods to free up space on your Windows device. 

Option 1: Enable Storage Sense 

• Go to Settings > System > Storage, turn on Storage Sense, and configure it to automatically delete temp files, Recycle Bin items after 30 days, and unused cloud files. Run it manually now for immediate results 

Option 2: Uninstall Unused Apps 

• Open Settings > Apps > Installed apps, sort by size, and remove programs you no longer need via the three-dot menu. Check for large games or tools first 

Option 3: Clear Downloads and Temp Folders 

• Delete old files from Downloads folder and %temp% (type in Run dialog via Win+R). Empty Recycle Bin afterward 

Option 4: Optimize OneDrive 

• Turn on Files On-Demand to keep files in the cloud and download them only when needed. 
• Right‑click a large folder > select Free up space to make the files online‑only. 

I really hope that the information I gave above was helpful to you. Please feel free to reply below and let me know if you have further concern on this matter.    

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