diff --git a/lnbits/core/views/api.py b/lnbits/core/views/api.py
index 349be809d..9acfa9cd9 100644
--- a/lnbits/core/views/api.py
+++ b/lnbits/core/views/api.py
@@ -798,19 +798,23 @@ async def api_install_extension(
         with zipfile.ZipFile(ext_zip_file, "r") as zip_ref:
             zip_ref.extractall("lnbits/extensions")
 
-        ext_upgrade_dir = os.path.join("lnbits/upgrades", f"{extension.id}-{extension.hash}")
+        ext_upgrade_dir = os.path.join(
+            "lnbits/upgrades", f"{extension.id}-{extension.hash}"
+        )
         os.makedirs("lnbits/upgrades", exist_ok=True)
         shutil.rmtree(ext_upgrade_dir, True)
         with zipfile.ZipFile(ext_zip_file, "r") as zip_ref:
             zip_ref.extractall(ext_upgrade_dir)
 
+        module_name = f"lnbits.extensions.{ext_id}"
+        module_installed = module_name in sys.modules
         # todo: is admin only
         ext = Extension(
             code=extension.id,
             is_valid=True,
             is_admin_only=False,
             name=extension.name,
-            hash=extension.hash,
+            hash=extension.hash if module_installed else "",
         )
 
         current_versions = await get_dbversions()