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Stuck in PreOS Mode

I have installed windows on my MacBook Air 2019 and installed Aomei to make some space so I could install games off steam. 

When I made the partition and restarted I am not stuck in:

AOMEI Partition Assistant PreOS Mode, it keeps looping from that to the windows screen attempting to start. 

It says information code 13 
the description is: No operations need to be processed. Please reboot and re run Partition Assistant to finish your operations 

I have read some other posts on this and it says to get another computer 3rd party in and delete the file named ampa.exe. I am unable to 3rd party in because I don’t have the means to. Where do I go now? 

Please email me at [email protected]


  • edited July 2023
    "Installed Aomei to make some space". Do you mean you installed Partition Assistant (PA) to resize the Windows C system partition? You may easily resize an NTFS partition under normal circumstances using Disk Management (DM), and it runs much faster than PA for that task. There are rare situations where PA is better than DM for resizing, but normally use DM first for that task.
    For the rare situations that you need to use PA to resize, instead of DM, Aomei recommends using WinPE mode when rebooting, instead of PreOS mode.
    If you have tried both of these suggestions and they are not working, you could try instead to use a PA WinPE USB, and if you are using a VM, you could just use a DVD ISO, that is easier for VMs.
    For your safety, please do not post personal information. Let us know how you resolved this issue, Nei, thank you!
    Partition Assistant WinPE USB:
    Add custom drivers, such as NVMe, if necessary.

    Aomei WinPE Builder 2.0 USB, includes: Partition Assistant, Backupper, Recuva, OSF Mount, CPU-Z, Bootice. Does not support any additional drivers, such as some internal NVMe disks.
    Free tools not from Aomei:

    Hirens Boot PE - live USB tool suite
    160 utilities, old BU 6.5.1, PA 9.2.1. To add custom drivers, such as NVMe, simply put them into the “CustomDrivers” folder. Hirens is not recommended in combination with Ventoy USB.

  • @Nei, Please try to power down your computer, and then reboot it to check again. You can try to power down and reboot the computer multiple times.
    If it still stuck in PreOS Mode, you might need to create a WinPE bootable media on a working computer, and then boot the computer from WinPE to delete ampa.exe file under C:\Windows.
    Maybe you can use AOMEI PE Builder to create WinPE:
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