diff --git a/sbysrc/sby.py b/sbysrc/sby.py
index 315aa55..bc95900 100644
--- a/sbysrc/sby.py
+++ b/sbysrc/sby.py
@@ -224,6 +224,16 @@ def read_sbyconfig(sbydata, taskname):
             found_task_tag = False
             task_skip_line = False
 
+            windows_drive_path = re.match(r"^([A-Za-z]):[\\/]", line)
+            if windows_drive_path and windows_drive_path.group(1) in task_tags_all:
+                drive = windows_drive_path.group(1)
+                print(
+                    f'ERROR: Task or group name "{drive}" conflicts with Windows path "{line}". '
+                    "Rename the task or group.",
+                    file=sys.stderr,
+                )
+                sys.exit(1)
+
             for t in task_tags_all:
                 if line.startswith(t+":"):
                     line = line[len(t)+1:].lstrip()
diff --git a/tests/config_parser/windows_drive_task_names.py b/tests/config_parser/windows_drive_task_names.py
new file mode 100644
index 0000000..6ea08ae
--- /dev/null
+++ b/tests/config_parser/windows_drive_task_names.py
@@ -0,0 +1,57 @@
+import subprocess
+import sys
+
+
+def run_sby(sby_main, config):
+    return subprocess.run(
+        [sys.executable, sby_main, "--dumptasks"],
+        input=config,
+        capture_output=True,
+        text=True,
+    )
+
+
+def expect_drive_conflict(sby_main, tasks, drive_path):
+    result = run_sby(
+        sby_main,
+        f"""[tasks]
+{tasks}
+
+[options]
+mode prep
+
+[files]
+{drive_path}
+""",
+    )
+
+    drive = drive_path[0]
+    expected = (
+        f'ERROR: Task or group name "{drive}" conflicts with Windows path '
+        f'"{drive_path}". Rename the task or group.'
+    )
+    assert result.returncode == 1, result
+    assert expected in result.stderr, result.stderr
+
+
+def main():
+    sby_main = sys.argv[1]
+
+    expect_drive_conflict(sby_main, "C", r"C:\src\example.sv")
+    expect_drive_conflict(sby_main, "task D", "D:/src/example.sv")
+
+    result = run_sby(
+        sby_main,
+        """[tasks]
+C
+
+[options]
+C: mode prep
+""",
+    )
+    assert result.returncode == 0, result
+    assert "C" in result.stdout.splitlines(), result.stdout
+
+
+if __name__ == "__main__":
+    main()
diff --git a/tests/config_parser/windows_drive_task_names.sby b/tests/config_parser/windows_drive_task_names.sby
new file mode 100644
index 0000000..85f2b12
--- /dev/null
+++ b/tests/config_parser/windows_drive_task_names.sby
@@ -0,0 +1,2 @@
+[options]
+mode prep
diff --git a/tests/config_parser/windows_drive_task_names.sh b/tests/config_parser/windows_drive_task_names.sh
new file mode 100644
index 0000000..86eec4b
--- /dev/null
+++ b/tests/config_parser/windows_drive_task_names.sh
@@ -0,0 +1,4 @@
+#!/bin/bash
+set -e
+
+python3 windows_drive_task_names.py "$SBY_MAIN"