diff --git a/gateway/platforms/base.py b/gateway/platforms/base.py
index 6979a869148..e1b677f12a1 100644
--- a/gateway/platforms/base.py
+++ b/gateway/platforms/base.py
@@ -1191,10 +1191,12 @@ _MEDIA_EXT_ALTERNATION = "|".join(
 # bare-path detector (extract_local_files) downstream rather than silently
 # deleted. Shared by the non-streaming dispatch path and the streaming
 # consumer so both behave identically.
+# Path anchors: ``~/`` (Unix home-relative), ``/`` (Unix absolute),
+# ``X:\\`` or ``X:/`` (Windows drive-letter absolute — #34632).
 MEDIA_TAG_CLEANUP_RE = re.compile(
     r'''[`"']?MEDIA:\s*'''
     r'''(?P<path>`[^`\n]+`|"[^"\n]+"|'[^'\n]+'|'''
-    r'''(?:~/|/)\S+(?:[^\S\n]+\S+)*?\.(?:''' + _MEDIA_EXT_ALTERNATION + r'''))'''
+    r'''(?:~/|/|[A-Za-z]:[/\\])\S+(?:[^\S\n]+\S+)*?\.(?:''' + _MEDIA_EXT_ALTERNATION + r'''))'''
     r'''(?=[\s`"',;:)\]}]|$)[`"']?''',
     re.IGNORECASE,
 )
@@ -2665,9 +2667,10 @@ class BasePlatformAdapter(ABC):
 
         # (?<![/:\w.]) prevents matching inside URLs (e.g. https://…/img.png)
         #             and relative paths (./foo.png)
-        # (?:~/|/)    anchors to absolute or home-relative paths
+        # (?:~/|/)    anchors to absolute or home-relative Unix paths
+        # (?:[A-Za-z]:[/\\]) anchors to Windows drive-letter paths (#34632)
         path_re = re.compile(
-            r'(?<![/:\w.])(?:~/|/)(?:[\w.\-]+/)*[\w.\-]+\.(?:' + ext_part + r')\b',
+            r'(?<![/:\w.])(?:~/|/|[A-Za-z]:[/\\])(?:[\w.\-]+[/\\])*[\w.\-]+\.(?:' + ext_part + r')\b',
             re.IGNORECASE,
         )
 
diff --git a/gateway/run.py b/gateway/run.py
index 3db565895ba..6adb98b8e20 100644
--- a/gateway/run.py
+++ b/gateway/run.py
@@ -17320,7 +17320,7 @@ class GatewayRunner:
                     _hc = _hm.get("content", "")
                     if "MEDIA:" in _hc:
                         _TOOL_MEDIA_RE = re.compile(
-                            r'MEDIA:((?:/|~\/)\S+\.(?:png|jpe?g|gif|webp|'
+                            r'MEDIA:((?:[A-Za-z]:[/\\]|/|~\/)\S+\.(?:png|jpe?g|gif|webp|'
                             r'mp4|mov|avi|mkv|webm|ogg|opus|mp3|wav|m4a|'
                             r'flac|epub|pdf|zip|rar|7z|docx?|xlsx?|pptx?|'
                             r'txt|csv|apk|ipa))',
@@ -17646,7 +17646,7 @@ class GatewayRunner:
                         content = msg.get("content", "")
                         if "MEDIA:" in content:
                             _TOOL_MEDIA_RE = re.compile(
-                                r'MEDIA:((?:/|~\/)\S+\.(?:png|jpe?g|gif|webp|'
+                                r'MEDIA:((?:[A-Za-z]:[/\\]|/|~\/)\S+\.(?:png|jpe?g|gif|webp|'
                                 r'mp4|mov|avi|mkv|webm|ogg|opus|mp3|wav|m4a|'
                                 r'flac|epub|pdf|zip|rar|7z|docx?|xlsx?|pptx?|'
                                 r'txt|csv|apk|ipa))',
diff --git a/tests/gateway/test_platform_base.py b/tests/gateway/test_platform_base.py
index e0f2c80cb04..2cc8118b7b2 100644
--- a/tests/gateway/test_platform_base.py
+++ b/tests/gateway/test_platform_base.py
@@ -361,6 +361,45 @@ class TestExtractMedia:
         assert "[[audio_as_voice]]" not in cleaned
         assert "[[as_document]]" not in cleaned
 
+    # Windows path support — regression coverage for #34632
+
+    def test_media_tag_windows_backslash_path(self):
+        """extract_media should recognise Windows backslash paths."""
+        media, cleaned = BasePlatformAdapter.extract_media(
+            r"MEDIA:C:\Users\kotsu\file.pdf"
+        )
+        assert len(media) == 1
+        assert media[0][0].endswith("file.pdf")
+
+    def test_media_tag_windows_forward_slash_path(self):
+        """extract_media should recognise Windows forward-slash paths."""
+        media, cleaned = BasePlatformAdapter.extract_media(
+            "MEDIA:C:/Users/kotsu/file.pdf"
+        )
+        assert len(media) == 1
+        assert media[0][0].endswith("file.pdf")
+
+    def test_media_tag_windows_drive_root(self):
+        """extract_media should recognise a path at the drive root."""
+        media, cleaned = BasePlatformAdapter.extract_media(
+            r"MEDIA:D:\report.md"
+        )
+        assert len(media) == 1
+        assert media[0][0].endswith("report.md")
+
+    def test_media_tag_unix_paths_still_work(self):
+        """Unix absolute and tilde paths must still extract after Windows change."""
+        for content in ["MEDIA:/tmp/audio.ogg", r"MEDIA:~/docs/notes.md"]:
+            media, _ = BasePlatformAdapter.extract_media(content)
+            assert len(media) == 1, f"Failed for: {content}"
+
+    def test_relative_path_still_ignored(self):
+        """Relative Windows-style paths (no drive letter) must not match."""
+        media, _ = BasePlatformAdapter.extract_media(
+            r"MEDIA:Users\kotsu\file.pdf"
+        )
+        assert media == []
+
 
 class TestMediaExtensionAllowlistParity:
     """Regression coverage for issue #34517 — the MEDIA: extension black hole.
diff --git a/tests/gateway/test_run_tool_media_re.py b/tests/gateway/test_run_tool_media_re.py
new file mode 100644
index 00000000000..67b496d1ddc
--- /dev/null
+++ b/tests/gateway/test_run_tool_media_re.py
@@ -0,0 +1,147 @@
+"""Tests for _TOOL_MEDIA_RE regex patterns in gateway/run.py.
+
+Issue #34632: The _TOOL_MEDIA_RE patterns in GatewayRunner used (?:/|~\/) to
+anchor paths, which only matched Unix-style absolute and home-relative paths.
+Windows absolute paths (C:\\Users\\..., D:/...) were silently ignored, causing
+MEDIA directive delivery to fail on Windows.
+
+Fix: Add [A-Za-z]:[/\\\\] as a third anchor alternative in both patterns.
+
+Two identical _TOOL_MEDIA_RE patterns exist in run.py:
+1. History scanning (~L17223): collects already-seen media paths
+2. Result scanning (~L17549): extracts new media tags from agent output
+
+This test file validates that both equivalent regex patterns correctly match
+Windows paths while preserving existing Unix path matching behavior.
+"""
+
+import re
+
+import pytest
+
+
+# Reconstruct the exact _TOOL_MEDIA_RE pattern from gateway/run.py
+# The pattern is built by concatenating raw string parts:
+#   r'MEDIA:((?:[A-Za-z]:[/\\]|/|~\/)\S+\.(?:png|...))'
+_TOOL_MEDIA_RE = re.compile(
+    r'MEDIA:((?:[A-Za-z]:[/\\]|/|~\/)\S+\.(?:png|jpe?g|gif|webp|'
+    r'mp4|mov|avi|mkv|webm|ogg|opus|mp3|wav|m4a|'
+    r'flac|epub|pdf|zip|rar|7z|docx?|xlsx?|pptx?|'
+    r'txt|csv|apk|ipa))',
+    re.IGNORECASE,
+)
+
+
+# Reconstruct the pre-fix pattern (without Windows anchor) for regression proof
+_TOOL_MEDIA_RE_PRE_FIX = re.compile(
+    r'MEDIA:((?:/|~\/)\S+\.(?:png|jpe?g|gif|webp|'
+    r'mp4|mov|avi|mkv|webm|ogg|opus|mp3|wav|m4a|'
+    r'flac|epub|pdf|zip|rar|7z|docx?|xlsx?|pptx?|'
+    r'txt|csv|apk|ipa))',
+    re.IGNORECASE,
+)
+
+
+class TestToolMediaReWindowsPaths:
+    """Issue #34632: _TOOL_MEDIA_RE must match Windows absolute paths."""
+
+    # ── Positive: Windows paths now match ──────────────────────────
+
+    @pytest.mark.parametrize("media_tag, expected_path", [
+        # Windows backslash paths
+        ("MEDIA:C:\\Users\\test\\image.png", "C:\\Users\\test\\image.png"),
+        ("MEDIA:D:\\data\\report.pdf", "D:\\data\\report.pdf"),
+        ("MEDIA:E:\\Photos\\vacation.jpg", "E:\\Photos\\vacation.jpg"),
+        # Windows forward-slash paths
+        ("MEDIA:C:/Users/test/image.png", "C:/Users/test/image.png"),
+        ("MEDIA:D:/data/report.pdf", "D:/data/report.pdf"),
+        # Mixed separators
+        ("MEDIA:C:\\Users/test\\image.webp", "C:\\Users/test\\image.webp"),
+        # Various extensions
+        ("MEDIA:F:\\videos\\clip.mp4", "F:\\videos\\clip.mp4"),
+        ("MEDIA:G:\\audio\\song.mp3", "G:\\audio\\song.mp3"),
+        ("MEDIA:H:\\docs\\sheet.xlsx", "H:\\docs\\sheet.xlsx"),
+        ("MEDIA:Z:\\archive\\backup.zip", "Z:\\archive\\backup.zip"),
+    ])
+    def test_windows_paths_match(self, media_tag, expected_path):
+        """Windows absolute paths with drive letters are matched."""
+        match = _TOOL_MEDIA_RE.search(media_tag)
+        assert match is not None, f"Should match: {media_tag}"
+        assert match.group(1) == expected_path
+
+    # ── Positive: Unix paths still match ───────────────────────────
+
+    @pytest.mark.parametrize("media_tag, expected_path", [
+        ("MEDIA:/tmp/output.png", "/tmp/output.png"),
+        ("MEDIA:/var/log/report.pdf", "/var/log/report.pdf"),
+        ("MEDIA:/home/user/docs/file.txt", "/home/user/docs/file.txt"),
+        # Home-relative
+        ("MEDIA:~/Downloads/image.jpg", "~/Downloads/image.jpg"),
+        ("MEDIA:~/Documents/report.pdf", "~/Documents/report.pdf"),
+    ])
+    def test_unix_paths_still_match(self, media_tag, expected_path):
+        """Unix-style absolute and home-relative paths still match."""
+        match = _TOOL_MEDIA_RE.search(media_tag)
+        assert match is not None, f"Should match: {media_tag}"
+        assert match.group(1) == expected_path
+
+    # ── Negative: invalid paths don't match ────────────────────────
+
+    @pytest.mark.parametrize("text", [
+        "No MEDIA tag here",
+        "MEDIA:relative/path/file.png",       # relative path, no anchor
+        "MEDIA:file.png",                      # no directory
+        "MEDIA:C:file.png",                    # drive letter but no separator
+        "MEDIA:/path/to/file.unknown",         # unsupported extension
+        "MEDIA:/path/to/file",                 # no extension
+        "MEDIA:",                               # empty path
+    ])
+    def test_invalid_paths_dont_match(self, text):
+        """Non-MEDIA text, relative paths, and unsupported extensions are ignored."""
+        match = _TOOL_MEDIA_RE.search(text)
+        assert match is None, f"Should NOT match: {text}"
+
+    # ── Negative/preserved: old pattern rejects Windows paths ──────
+
+    @pytest.mark.parametrize("media_tag", [
+        "MEDIA:C:\\Users\\test\\image.png",
+        "MEDIA:D:/data/report.pdf",
+        "MEDIA:C:\\path\\file.jpg",
+    ])
+    def test_pre_fix_pattern_rejects_windows(self, media_tag):
+        """The pre-fix pattern (without Windows anchor) does NOT match Windows paths.
+        This proves the fix is necessary — without it, these paths are silently ignored."""
+        match = _TOOL_MEDIA_RE_PRE_FIX.search(media_tag)
+        assert match is None, f"Pre-fix pattern should NOT match: {media_tag}"
+
+    # ── Edge cases ─────────────────────────────────────────────────
+
+    def test_multiple_media_tags_in_content(self):
+        """Multiple MEDIA tags in the same content are all found."""
+        content = (
+            "Some text MEDIA:C:\\path\\img.png and more MEDIA:/tmp/out.pdf trailing"
+        )
+        matches = list(_TOOL_MEDIA_RE.finditer(content))
+        assert len(matches) == 2
+        paths = [m.group(1) for m in matches]
+        assert "C:\\path\\img.png" in paths
+        assert "/tmp/out.pdf" in paths
+
+    def test_case_insensitive_drive_letter(self):
+        """Drive letters are case-insensitive due to re.IGNORECASE."""
+        match_lower = _TOOL_MEDIA_RE.search("MEDIA:c:\\path\\file.png")
+        match_upper = _TOOL_MEDIA_RE.search("MEDIA:C:\\path\\file.png")
+        assert match_lower is not None
+        assert match_upper is not None
+        assert match_lower.group(1).lower() == match_upper.group(1).lower()
+
+    @pytest.mark.parametrize("media_tag", [
+        "MEDIA:C:\\path\\file.jpeg",
+        "MEDIA:C:\\path\\file.JPG",
+        "MEDIA:C:\\path\\file.GIF",
+        "MEDIA:C:\\path\\file.MP4",
+    ])
+    def test_case_insensitive_extensions(self, media_tag):
+        """File extensions are matched case-insensitively."""
+        match = _TOOL_MEDIA_RE.search(media_tag)
+        assert match is not None, f"Should match: {media_tag}"