diff --git a/delta/test/test_files/delta.test b/delta/test/test_files/delta.test
index ac417984..4002a824 100644
--- a/delta/test/test_files/delta.test
+++ b/delta/test/test_files/delta.test
@@ -40,10 +40,12 @@ Alice|[52,24,31]|True|2020-05-17 00:00:00|{age: 25, gender: female}
 Bob|[15,66,72]|False|2011-03-22 00:00:00|{age: 22, gender: male}
 Carol|[29,24,11]||2001-04-15 00:00:00|{age: 33, gender: female}
 
+# Core binder passes the source through verbatim for extension-provided formats, so the
+# error for a non-existent table path now comes from the Delta scan itself.
 -LOG InvalidDeltaPath
 -STATEMENT LOAD FROM '${LBUG_ROOT_DIRECTORY}/student'(file_format='delta') RETURN *
 ---- error
-Binder exception: No file found that matches the pattern: ${LBUG_ROOT_DIRECTORY}/student.
+IO Error: Hit DeltaKernel FFI error (from: While trying to read from delta table: '${LBUG_ROOT_DIRECTORY}/student'): Hit error: 2 (Generic) with message (Not a Delta table: {})
 
 -LOG InvalidDeltaTable
 -STATEMENT LOAD FROM '${LBUG_ROOT_DIRECTORY}/src' (file_format='delta') RETURN *
diff --git a/httpfs/test/httpfs_test.cpp b/httpfs/test/httpfs_test.cpp
index 44f9aa2f..d59fdff9 100644
--- a/httpfs/test/httpfs_test.cpp
+++ b/httpfs/test/httpfs_test.cpp
@@ -39,6 +39,18 @@ class LocalHttpServer {
             }
             return httplib::Server::HandlerResponse::Unhandled;
         });
+        // The vendored httplib enables SO_REUSEPORT by default on Linux, which
+        // allows multiple sockets to bind the same port and load-balances
+        // connections between them. When ctest runs these tests in parallel,
+        // two processes' servers then share a port and requests land on the
+        // wrong server, making request counts flaky (observed as headCount()==0
+        // under `ctest -j10`). Restrict to SO_REUSEADDR so a second bind fails
+        // and the loop below picks a genuinely free port instead.
+        server_.set_socket_options([](socket_t sock) {
+            int yes = 1;
+            setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, reinterpret_cast<const char*>(&yes),
+                sizeof(yes));
+        });
         for (int port = 18123; port < 18153; ++port) {
             if (server_.bind_to_port("127.0.0.1", port)) {
                 port_ = port;
diff --git a/iceberg/test/test_files/iceberg.test b/iceberg/test/test_files/iceberg.test
index a0ed3279..f68be972 100644
--- a/iceberg/test/test_files/iceberg.test
+++ b/iceberg/test/test_files/iceberg.test
@@ -50,10 +50,12 @@ Yale|6|190.700000
 #Bob|[15,66,72]|False|2011-03-22 00:00:00|{age: 22, gender: male}
 #Carol|[29,24,11]||2001-04-15 00:00:00|{age: 33, gender: female}
 
+# Core binder passes the source through verbatim for extension-provided formats, so the
+# error for a non-existent table path now comes from the Iceberg scan itself.
 -LOG InvalidIcebergPath
 -STATEMENT LOAD FROM '${LBUG_ROOT_DIRECTORY}/student' (file_format='iceberg', allow_moved_paths=true) RETURN *
----- error
-Binder exception: No file found that matches the pattern: ${LBUG_ROOT_DIRECTORY}/student.
+---- error(regex)
+IO Error: Cannot open file ".*": (The system cannot find the path specified.*|No such file or directory)
 
 -LOG InvalidIcebergTable
 -STATEMENT LOAD FROM '${LBUG_ROOT_DIRECTORY}/src' (file_format='iceberg', allow_moved_paths=true) RETURN *