diff --git a/src/internal/syscall/windows/syscall_windows.go b/src/internal/syscall/windows/syscall_windows.go
index a02c96c8f0..03ceb5803f 100644
--- a/src/internal/syscall/windows/syscall_windows.go
+++ b/src/internal/syscall/windows/syscall_windows.go
@@ -10,6 +10,12 @@ import (
 	"unsafe"
 )
 
+// CanUseLongPaths is true when the OS supports opting into
+// proper long path handling without the need for fixups.
+//
+//go:linkname CanUseLongPaths
+var CanUseLongPaths bool
+
 // UTF16PtrToString is like UTF16ToString, but takes *uint16
 // as a parameter instead of []uint16.
 func UTF16PtrToString(p *uint16) string {
diff --git a/src/os/export_windows_test.go b/src/os/export_windows_test.go
index 6e1188816b..2e5904b3f5 100644
--- a/src/os/export_windows_test.go
+++ b/src/os/export_windows_test.go
@@ -8,7 +8,6 @@ package os
 
 var (
 	FixLongPath        = fixLongPath
-	CanUseLongPaths    = canUseLongPaths
 	NewConsoleFile     = newConsoleFile
 	CommandLineToArgv  = commandLineToArgv
 	AllowReadDirFileID = &allowReadDirFileID
diff --git a/src/os/path_windows.go b/src/os/path_windows.go
index 0522025148..98139679d4 100644
--- a/src/os/path_windows.go
+++ b/src/os/path_windows.go
@@ -4,6 +4,8 @@
 
 package os
 
+import "internal/syscall/windows"
+
 const (
 	PathSeparator     = '\\' // OS-specific path separator
 	PathListSeparator = ';'  // OS-specific path list separator
@@ -128,10 +130,6 @@ func dirname(path string) string {
 	return vol + dir
 }
 
-// This is set via go:linkname on runtime.canUseLongPaths, and is true when the OS
-// supports opting into proper long path handling without the need for fixups.
-var canUseLongPaths bool
-
 // fixLongPath returns the extended-length (\\?\-prefixed) form of
 // path when needed, in order to avoid the default 260 character file
 // path limit imposed by Windows. If path is not easily converted to
@@ -141,7 +139,7 @@ var canUseLongPaths bool
 //
 // See https://learn.microsoft.com/en-us/windows/win32/fileio/naming-a-file#maximum-path-length-limitation
 func fixLongPath(path string) string {
-	if canUseLongPaths {
+	if windows.CanUseLongPaths {
 		return path
 	}
 	// Do nothing (and don't allocate) if the path is "short".
diff --git a/src/os/path_windows_test.go b/src/os/path_windows_test.go
index 4e5e501d1f..6fa864a98d 100644
--- a/src/os/path_windows_test.go
+++ b/src/os/path_windows_test.go
@@ -16,7 +16,7 @@ import (
 )
 
 func TestFixLongPath(t *testing.T) {
-	if os.CanUseLongPaths {
+	if windows.CanUseLongPaths {
 		return
 	}
 	t.Parallel()
diff --git a/src/runtime/os_windows.go b/src/runtime/os_windows.go
index 7e9bbd04f2..ca443ae0c3 100644
--- a/src/runtime/os_windows.go
+++ b/src/runtime/os_windows.go
@@ -20,7 +20,6 @@ const (
 //go:cgo_import_dynamic runtime._AddVectoredExceptionHandler AddVectoredExceptionHandler%2 "kernel32.dll"
 //go:cgo_import_dynamic runtime._CloseHandle CloseHandle%1 "kernel32.dll"
 //go:cgo_import_dynamic runtime._CreateEventA CreateEventA%4 "kernel32.dll"
-//go:cgo_import_dynamic runtime._CreateFileA CreateFileA%7 "kernel32.dll"
 //go:cgo_import_dynamic runtime._CreateIoCompletionPort CreateIoCompletionPort%4 "kernel32.dll"
 //go:cgo_import_dynamic runtime._CreateThread CreateThread%6 "kernel32.dll"
 //go:cgo_import_dynamic runtime._CreateWaitableTimerA CreateWaitableTimerA%3 "kernel32.dll"
@@ -78,7 +77,6 @@ var (
 	_AddVectoredExceptionHandler,
 	_CloseHandle,
 	_CreateEventA,
-	_CreateFileA,
 	_CreateIoCompletionPort,
 	_CreateThread,
 	_CreateWaitableTimerA,
@@ -418,29 +416,14 @@ func initHighResTimer() {
 	}
 }
 
-//go:linkname canUseLongPaths os.canUseLongPaths
+//go:linkname canUseLongPaths internal/syscall/windows.CanUseLongPaths
 var canUseLongPaths bool
 
-// We want this to be large enough to hold the contents of sysDirectory, *plus*
-// a slash and another component that itself is greater than MAX_PATH.
-var longFileName [(_MAX_PATH+1)*2 + 1]byte
-
-// initLongPathSupport initializes the canUseLongPaths variable, which is
-// linked into os.canUseLongPaths for determining whether or not long paths
-// need to be fixed up. In the best case, this function is running on newer
-// Windows 10 builds, which have a bit field member of the PEB called
-// "IsLongPathAwareProcess." When this is set, we don't need to go through the
-// error-prone fixup function in order to access long paths. So this init
-// function first checks the Windows build number, sets the flag, and then
-// tests to see if it's actually working. If everything checks out, then
-// canUseLongPaths is set to true, and later when called, os.fixLongPath
-// returns early without doing work.
+// initLongPathSupport enables long path support.
 func initLongPathSupport() {
 	const (
 		IsLongPathAwareProcess = 0x80
 		PebBitFieldOffset      = 3
-		OPEN_EXISTING          = 3
-		ERROR_PATH_NOT_FOUND   = 3
 	)
 
 	// Check that we're ≥ 10.0.15063.
@@ -451,41 +434,11 @@ func initLongPathSupport() {
 	}
 
 	// Set the IsLongPathAwareProcess flag of the PEB's bit field.
+	// This flag is not documented, but it's known to be used
+	// by Windows to enable long path support.
 	bitField := (*byte)(unsafe.Pointer(stdcall0(_RtlGetCurrentPeb) + PebBitFieldOffset))
-	originalBitField := *bitField
 	*bitField |= IsLongPathAwareProcess
 
-	// Check that this actually has an effect, by constructing a large file
-	// path and seeing whether we get ERROR_PATH_NOT_FOUND, rather than
-	// some other error, which would indicate the path is too long, and
-	// hence long path support is not successful. This whole section is NOT
-	// strictly necessary, but is a nice validity check for the near to
-	// medium term, when this functionality is still relatively new in
-	// Windows.
-	targ := longFileName[len(longFileName)-33 : len(longFileName)-1]
-	if readRandom(targ) != len(targ) {
-		readTimeRandom(targ)
-	}
-	start := copy(longFileName[:], sysDirectory[:sysDirectoryLen])
-	const dig = "0123456789abcdef"
-	for i := 0; i < 32; i++ {
-		longFileName[start+i*2] = dig[longFileName[len(longFileName)-33+i]>>4]
-		longFileName[start+i*2+1] = dig[longFileName[len(longFileName)-33+i]&0xf]
-	}
-	start += 64
-	for i := start; i < len(longFileName)-1; i++ {
-		longFileName[i] = 'A'
-	}
-	stdcall7(_CreateFileA, uintptr(unsafe.Pointer(&longFileName[0])), 0, 0, 0, OPEN_EXISTING, 0, 0)
-	// The ERROR_PATH_NOT_FOUND error value is distinct from
-	// ERROR_FILE_NOT_FOUND or ERROR_INVALID_NAME, the latter of which we
-	// expect here due to the final component being too long.
-	if getlasterror() == ERROR_PATH_NOT_FOUND {
-		*bitField = originalBitField
-		println("runtime: warning: IsLongPathAwareProcess failed to enable long paths; proceeding in fixup mode")
-		return
-	}
-
 	canUseLongPaths = true
 }