diff --git a/source/synthDrivers/oneCore.py b/source/synthDrivers/oneCore.py
index 02d3f888eb5..f4b0490dea2 100644
--- a/source/synthDrivers/oneCore.py
+++ b/source/synthDrivers/oneCore.py
@@ -117,13 +117,8 @@ class SynthDriver(SynthDriver):
 
 	@classmethod
 	def check(cls):
-		if not hasattr(sys, "frozen"):
-			# #3793: Source copies don't report the correct version on Windows 10 because Python isn't manifested for higher versions.
-			# We want this driver to work for source copies on Windows 10, so just return True here.
-			# If this isn't in fact Windows 10, it will fail when constructed, which is okay.
-			return True
-		# For binary copies, only present this as an available synth if this is Windows 10.
-		return winVersion.winVersion.major >= 10
+		# Only present this as an available synth if this is Windows 10.
+		return winVersion.isWin10()
 
 	def _get_supportsProsodyOptions(self):
 		self.supportsProsodyOptions = self._dll.ocSpeech_supportsProsodyOptions()
diff --git a/source/winVersion.py b/source/winVersion.py
index 242403ee18d..153796c1c7c 100644
--- a/source/winVersion.py
+++ b/source/winVersion.py
@@ -30,7 +30,6 @@ def isUwpOcrAvailable():
 def isWin10(version=1507, atLeast=True):
 	"""
 	Returns True if NVDA is running on the supplied release version of Windows 10. If no argument is supplied, returns True for all public Windows 10 releases.
-	@note: this function will always return False for source copies of NVDA due to a Python bug.
 	@param version: a release version of Windows 10 (such as 1903).
 	@param atLeast: return True if NVDA is running on at least this Windows 10 build (i.e. this version or higher).
 	"""