diff --git a/.appveyor.yml b/.appveyor.yml
index a6c07776..d7edc0d7 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -21,7 +21,7 @@ environment:
         - {APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015, PY_VER: "36", PY_ARCH: "64"}
 
     OPENSSL_VERSION: "1_1_1h"
-    POSTGRES_VERSION: "11_4"
+    POSTGRES_VERSION: "13_0"
 
     PSYCOPG2_TESTDB: psycopg2_test
     PSYCOPG2_TESTDB_USER: postgres
diff --git a/NEWS b/NEWS
index 7df532a3..f7e467b5 100644
--- a/NEWS
+++ b/NEWS
@@ -5,6 +5,10 @@ What's new in psycopg 2.9
 -------------------------
 
 - Dropped support for Python 2.7, 3.4, 3.5 (:tickets:#1198, #1000, #1197).
+- Reclassified SQLSTATE connection exceptions (08XXX) as
+  `~psycopg2.errors.OperationalError` (subclass of previously used
+  `~psycopg2.errors.DatabaseError`) (:ticket:`#1148`).
+
 
 What's new in psycopg 2.8.6
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/psycopg/error_type.c b/psycopg/error_type.c
index 37b4d4ae..60b2c48e 100644
--- a/psycopg/error_type.c
+++ b/psycopg/error_type.c
@@ -65,6 +65,8 @@ base_exception_from_sqlstate(const char *sqlstate)
     switch (sqlstate[0]) {
     case '0':
         switch (sqlstate[1]) {
+        case '8': /* Class 08 - Connection Exception */
+            return OperationalError;
         case 'A': /* Class 0A - Feature Not Supported */
             return NotSupportedError;
         }
diff --git a/scripts/appveyor.cache_rebuild b/scripts/appveyor.cache_rebuild
index 432d68ee..419eb94d 100644
--- a/scripts/appveyor.cache_rebuild
+++ b/scripts/appveyor.cache_rebuild
@@ -12,7 +12,7 @@ OpenSSL
         Version: 1.1.1h
 
 PostgreSQL
-        Version: 11.4
+        Version: 13.0
 
 
 NOTE: to zap the cache manually you can also use:
diff --git a/scripts/appveyor.py b/scripts/appveyor.py
index 7c9d3ba1..a5541835 100755
--- a/scripts/appveyor.py
+++ b/scripts/appveyor.py
@@ -53,6 +53,7 @@ def setup_build_env():
         str(opt.py_dir / 'Scripts'),
         r'C:\Strawberry\Perl\bin',
         r'C:\Program Files\Git\mingw64\bin',
+        str(opt.ssl_build_dir / 'bin'),
         os.environ['PATH'],
     ]
     setenv('PATH', os.pathsep.join(path))
@@ -212,7 +213,7 @@ def build_openssl():
         + ['no-shared', 'no-zlib', f'--prefix={top}', f'--openssldir={top}']
     )
 
-    run_command("nmake build_libs install_dev".split())
+    run_command("nmake build_libs install_sw".split())
 
     assert (top / 'lib' / 'libssl.lib').exists()
 
@@ -249,20 +250,6 @@ def build_libpq():
     pgbuild = opt.build_dir / f"postgres-REL_{ver}"
     os.chdir(pgbuild)
 
-    # Patch for OpenSSL 1.1 configuration. See:
-    # https://www.postgresql-archive.org/Compile-psql-9-6-with-SSL-Version-1-1-0-td6054118.html
-    assert Path("src/include/pg_config.h.win32").exists()
-    with open("src/include/pg_config.h.win32", 'a') as f:
-        print(
-            """
-#define HAVE_ASN1_STRING_GET0_DATA 1
-#define HAVE_BIO_GET_DATA 1
-#define HAVE_BIO_METH_NEW 1
-#define HAVE_OPENSSL_INIT_SSL 1
-""",
-            file=f,
-        )
-
     # Setup build config file (config.pl)
     os.chdir("src/tools/msvc")
     with open("config.pl", 'w') as f:
@@ -326,7 +313,7 @@ def build_psycopg():
     add_pg_config_path()
     run_python(
         ["setup.py", "build_ext", "--have-ssl"]
-        + ["-l", "libpgcommon", "-l", "libpgport"]
+        + ["-l", "libpgcommon libpgport"]
         + ["-L", opt.ssl_build_dir / 'lib']
         + ['-I', opt.ssl_build_dir / 'include']
     )
diff --git a/tests/test_errors.py b/tests/test_errors.py
index bd3e7fd6..ec2950c5 100755
--- a/tests/test_errors.py
+++ b/tests/test_errors.py
@@ -62,6 +62,13 @@ class ErrorsTests(ConnectingTestCase):
         with self.assertRaises(KeyError):
             errors.lookup('XXXXX')
 
+    def test_connection_exceptions_backwards_compatibility(self):
+        err = errors.lookup('08000')
+        # connection exceptions are classified as operational errors
+        self.assert_(issubclass(err, errors.OperationalError))
+        # previously these errors were classified only as DatabaseError
+        self.assert_(issubclass(err, errors.DatabaseError))
+
     def test_has_base_exceptions(self):
         excs = []
         for n in dir(psycopg2):