diff --git a/integration/conftest.py b/integration/conftest.py
index dc0107eea..33e7998c1 100644
--- a/integration/conftest.py
+++ b/integration/conftest.py
@@ -393,7 +393,7 @@ def alice(
             finalize=False,
         )
     )
-    await_client_ready(process)
+    pytest_twisted.blockon(await_client_ready(process))
 
     # 1. Create a new RW directory cap:
     cli(process, "create-alias", "test")
@@ -424,7 +424,7 @@ alice-key ssh-rsa {ssh_public_key} {rwcap}
 
     # 4. Restart the node with new SFTP config.
     pytest_twisted.blockon(process.restart_async(reactor, request))
-    await_client_ready(process)
+    pytest_twisted.blockon(await_client_ready(process))
     print(f"Alice pid: {process.transport.pid}")
     return process
 
@@ -439,7 +439,7 @@ def bob(reactor, temp_dir, introducer_furl, flog_gatherer, storage_nodes, reques
             storage=False,
         )
     )
-    await_client_ready(process)
+    pytest_twisted.blockon(await_client_ready(process))
     return process
 
 
diff --git a/integration/test_get_put.py b/integration/test_get_put.py
index 1b6c30072..f121d6284 100644
--- a/integration/test_get_put.py
+++ b/integration/test_get_put.py
@@ -4,7 +4,6 @@ and stdout.
 """
 
 from subprocess import Popen, PIPE, check_output, check_call
-import sys
 
 import pytest
 from pytest_twisted import ensureDeferred
@@ -50,6 +49,7 @@ def test_put_from_stdin(alice, get_put_alias, tmpdir):
     assert read_bytes(tempfile) == DATA
 
 
+@run_in_thread
 def test_get_to_stdout(alice, get_put_alias, tmpdir):
     """
     It's possible to upload a file, and then download it to stdout.
@@ -67,6 +67,7 @@ def test_get_to_stdout(alice, get_put_alias, tmpdir):
     assert p.wait() == 0
 
 
+@run_in_thread
 def test_large_file(alice, get_put_alias, tmp_path):
     """
     It's possible to upload and download a larger file.
@@ -85,10 +86,6 @@ def test_large_file(alice, get_put_alias, tmp_path):
     assert outfile.read_bytes() == tempfile.read_bytes()
 
 
-@pytest.mark.skipif(
-    sys.platform.startswith("win"),
-    reason="reconfigure() has issues on Windows"
-)
 @ensureDeferred
 async def test_upload_download_immutable_different_default_max_segment_size(alice, get_put_alias, tmpdir, request):
     """
diff --git a/integration/test_servers_of_happiness.py b/integration/test_servers_of_happiness.py
index b9de0c075..c63642066 100644
--- a/integration/test_servers_of_happiness.py
+++ b/integration/test_servers_of_happiness.py
@@ -31,7 +31,7 @@ def test_upload_immutable(reactor, temp_dir, introducer_furl, flog_gatherer, sto
         happy=7,
         total=10,
     )
-    util.await_client_ready(edna)
+    yield util.await_client_ready(edna)
 
     node_dir = join(temp_dir, 'edna')
 
diff --git a/integration/test_tor.py b/integration/test_tor.py
index c78fa8098..901858347 100644
--- a/integration/test_tor.py
+++ b/integration/test_tor.py
@@ -42,8 +42,8 @@ if PY2:
 def test_onion_service_storage(reactor, request, temp_dir, flog_gatherer, tor_network, tor_introducer_furl):
     carol = yield _create_anonymous_node(reactor, 'carol', 8008, request, temp_dir, flog_gatherer, tor_network, tor_introducer_furl)
     dave = yield _create_anonymous_node(reactor, 'dave', 8009, request, temp_dir, flog_gatherer, tor_network, tor_introducer_furl)
-    util.await_client_ready(carol, minimum_number_of_servers=2)
-    util.await_client_ready(dave, minimum_number_of_servers=2)
+    yield util.await_client_ready(carol, minimum_number_of_servers=2)
+    yield util.await_client_ready(dave, minimum_number_of_servers=2)
 
     # ensure both nodes are connected to "a grid" by uploading
     # something via carol, and retrieve it using dave.
diff --git a/integration/test_web.py b/integration/test_web.py
index 95a09a5f5..b3c4a8e5f 100644
--- a/integration/test_web.py
+++ b/integration/test_web.py
@@ -18,6 +18,7 @@ import allmydata.uri
 from allmydata.util import jsonbytes as json
 
 from . import util
+from .util import run_in_thread
 
 import requests
 import html5lib
@@ -25,6 +26,7 @@ from bs4 import BeautifulSoup
 
 from pytest_twisted import ensureDeferred
 
+@run_in_thread
 def test_index(alice):
     """
     we can download the index file
@@ -32,6 +34,7 @@ def test_index(alice):
     util.web_get(alice, u"")
 
 
+@run_in_thread
 def test_index_json(alice):
     """
     we can download the index file as json
@@ -41,6 +44,7 @@ def test_index_json(alice):
     json.loads(data)
 
 
+@run_in_thread
 def test_upload_download(alice):
     """
     upload a file, then download it via readcap
@@ -70,6 +74,7 @@ def test_upload_download(alice):
     assert str(data, "utf-8") == FILE_CONTENTS
 
 
+@run_in_thread
 def test_put(alice):
     """
     use PUT to create a file
@@ -89,6 +94,7 @@ def test_put(alice):
     assert cap.needed_shares == int(cfg.get_config("client", "shares.needed"))
 
 
+@run_in_thread
 def test_helper_status(storage_nodes):
     """
     successfully GET the /helper_status page
@@ -101,6 +107,7 @@ def test_helper_status(storage_nodes):
     assert str(dom.h1.string) == u"Helper Status"
 
 
+@run_in_thread
 def test_deep_stats(alice):
     """
     create a directory, do deep-stats on it and prove the /operations/
@@ -417,6 +424,7 @@ async def test_directory_deep_check(reactor, request, alice):
     assert dom is not None, "Operation never completed"
 
 
+@run_in_thread
 def test_storage_info(storage_nodes):
     """
     retrieve and confirm /storage URI for one storage node
@@ -428,6 +436,7 @@ def test_storage_info(storage_nodes):
     )
 
 
+@run_in_thread
 def test_storage_info_json(storage_nodes):
     """
     retrieve and confirm /storage?t=json URI for one storage node
@@ -442,6 +451,7 @@ def test_storage_info_json(storage_nodes):
     assert data[u"stats"][u"storage_server.reserved_space"] == 1000000000
 
 
+@run_in_thread
 def test_introducer_info(introducer):
     """
     retrieve and confirm /introducer URI for the introducer
@@ -460,6 +470,7 @@ def test_introducer_info(introducer):
     assert "subscription_summary" in data
 
 
+@run_in_thread
 def test_mkdir_with_children(alice):
     """
     create a directory using ?t=mkdir-with-children
diff --git a/integration/util.py b/integration/util.py
index 04c925abf..05fef8fed 100644
--- a/integration/util.py
+++ b/integration/util.py
@@ -430,6 +430,31 @@ class FileShouldVanishException(Exception):
         )
 
 
+def run_in_thread(f):
+    """Decorator for integration tests that runs code in a thread.
+
+    Because we're using pytest_twisted, tests that rely on the reactor are
+    expected to return a Deferred and use async APIs so the reactor can run.
+
+    In the case of the integration test suite, it launches nodes in the
+    background using Twisted APIs.  The nodes stdout and stderr is read via
+    Twisted code.  If the reactor doesn't run, reads don't happen, and
+    eventually the buffers fill up, and the nodes block when they try to flush
+    logs.
+
+    We can switch to Twisted APIs (treq instead of requests etc.), but
+    sometimes it's easier or expedient to just have a blocking test.  So this
+    decorator allows you to run the test in a thread, and the reactor can keep
+    running in the main thread.
+
+    See https://tahoe-lafs.org/trac/tahoe-lafs/ticket/3597 for tracking bug.
+    """
+    @wraps(f)
+    def test(*args, **kwargs):
+        return deferToThread(lambda: f(*args, **kwargs))
+    return test
+
+
 def await_file_contents(path, contents, timeout=15, error_if=None):
     """
     wait up to `timeout` seconds for the file at `path` (any path-like
@@ -555,6 +580,7 @@ def web_post(tahoe, uri_fragment, **kwargs):
     return resp.content
 
 
+@run_in_thread
 def await_client_ready(tahoe, timeout=10, liveness=60*2, minimum_number_of_servers=1):
     """
     Uses the status API to wait for a client-type node (in `tahoe`, a
@@ -622,30 +648,6 @@ def generate_ssh_key(path):
         f.write(s.encode("ascii"))
 
 
-def run_in_thread(f):
-    """Decorator for integration tests that runs code in a thread.
-
-    Because we're using pytest_twisted, tests that rely on the reactor are
-    expected to return a Deferred and use async APIs so the reactor can run.
-
-    In the case of the integration test suite, it launches nodes in the
-    background using Twisted APIs.  The nodes stdout and stderr is read via
-    Twisted code.  If the reactor doesn't run, reads don't happen, and
-    eventually the buffers fill up, and the nodes block when they try to flush
-    logs.
-
-    We can switch to Twisted APIs (treq instead of requests etc.), but
-    sometimes it's easier or expedient to just have a blocking test.  So this
-    decorator allows you to run the test in a thread, and the reactor can keep
-    running in the main thread.
-
-    See https://tahoe-lafs.org/trac/tahoe-lafs/ticket/3597 for tracking bug.
-    """
-    @wraps(f)
-    def test(*args, **kwargs):
-        return deferToThread(lambda: f(*args, **kwargs))
-    return test
-
 @frozen
 class CHK:
     """
@@ -792,16 +794,11 @@ async def reconfigure(reactor, request, node: TahoeProcess,
             )
 
     if changed:
-        # TODO reconfigure() seems to have issues on Windows. If you need to
-        # use it there, delete this assert and try to figure out what's going
-        # on...
-        assert not sys.platform.startswith("win")
-
         # restart the node
         print(f"Restarting {node.node_dir} for ZFEC reconfiguration")
         await node.restart_async(reactor, request)
         print("Restarted.  Waiting for ready state.")
-        await_client_ready(node)
+        await await_client_ready(node)
         print("Ready.")
     else:
         print("Config unchanged, not restarting.")
diff --git a/newsfragments/3988.minor b/newsfragments/3988.minor
new file mode 100644
index 000000000..e69de29bb