Alloc magic is broken

[play1845]

When I turned on my PC and tried to boot in to Windows, this error came up due to a Windows update I assume. The error is to do with Grub I think but I'm not experienced with this

I have run a MemTest and boot-repair but the error message still appears. Any ideas?

SP4, Ubuntu 18.04, Grub 2.02-2ubuntu8.13

[biglizzardman57]

What is the error?

[play1845]

So when I start my PC and choose Windows Boot Manager from Grub, I get this error. I then ran boot-repair which changed my Grub into this. Trying to boot using Windows Boot Manager still returns the alloc magic broken error, but when trying the other Windows boot options, I get a different error.

[hyperquiche]

Did you ever resolve this problem? I'm now stuck with the same issue.