diff --git a/bec_lib/bec_lib/lmfit_serializer.py b/bec_lib/bec_lib/lmfit_serializer.py
index dee651cf2..88d88210d 100644
--- a/bec_lib/bec_lib/lmfit_serializer.py
+++ b/bec_lib/bec_lib/lmfit_serializer.py
@@ -52,7 +52,7 @@ def serialize_lmfit_params(params: Parameters) -> dict:
         return {v.name: serialize_param_object(v) for v in params}
 
 
-def deserialize_param_object(obj: dict) -> Parameter:
+def deserialize_param_object(obj: dict) -> Parameters:
     """
     Deserialize dictionary representation of lmfit.Parameter object.
 
@@ -60,10 +60,24 @@ def deserialize_param_object(obj: dict) -> Parameter:
         obj (dict): Dictionary representation of the parameters
 
     Returns:
-        Parameter: Parameter object
+        Parameters: Parameters object
     """
     param = Parameters()
     for k, v in obj.items():
-        v.pop("name")
-        param.add(k, **v)
+        if isinstance(v, Parameter):
+            param.add(
+                k,
+                value=v.value,
+                vary=v.vary,
+                min=v.min,
+                max=v.max,
+                expr=v.expr,
+                brute_step=v.brute_step,
+            )
+            continue
+        if isinstance(v, dict):
+            v.pop("name", None)
+            v_copy = v.copy()
+            v_copy.pop("name", None)
+            param.add(k, **v_copy)
     return param
diff --git a/bec_lib/tests/test_lmfit_serializer.py b/bec_lib/tests/test_lmfit_serializer.py
index e73613d48..c5c487c6a 100644
--- a/bec_lib/tests/test_lmfit_serializer.py
+++ b/bec_lib/tests/test_lmfit_serializer.py
@@ -33,3 +33,19 @@ def test_serialize_lmfit_params():
 
     obj = deserialize_param_object(result)
     assert obj == params
+
+    # `name` is optional for deserialization (key is the param name)
+    result_without_names = {
+        k: {kk: vv for kk, vv in v.items() if kk != "name"} for k, v in result.items()
+    }
+    obj = deserialize_param_object(result_without_names)
+    assert obj == params
+
+
+def test_deserialize_param_object_accepts_parameter_objects():
+    params = lmfit.Parameters()
+    params.add("a", value=1.0, vary=True, min=-2.0, max=3.0)
+    params.add("b", value=2.0, vary=False)
+
+    obj = deserialize_param_object({"a": params["a"], "b": params["b"]})
+    assert obj == params
diff --git a/bec_server/bec_server/data_processing/lmfit1d_service.py b/bec_server/bec_server/data_processing/lmfit1d_service.py
index ab16dbfc8..260f5b6a4 100644
--- a/bec_server/bec_server/data_processing/lmfit1d_service.py
+++ b/bec_server/bec_server/data_processing/lmfit1d_service.py
@@ -41,6 +41,7 @@ def __init__(self, model: str, *args, continuous: bool = False, **kwargs):
         self.device_y = None
         self.signal_y = None
         self.parameters = None
+        self._parameter_override_names = []
         self.current_scan_item = None
         self.finished_id = None
         self.model = getattr(lmfit.models, model)()
@@ -169,6 +170,7 @@ def configure(
         data_y: np.ndarray = None,
         x_min: float = None,
         x_max: float = None,
+        parameters: dict | None = None,
         amplitude: lmfit.Parameter = None,
         center: lmfit.Parameter = None,
         sigma: lmfit.Parameter = None,
@@ -195,15 +197,59 @@ def configure(
 
         self.oversample = oversample
 
-        self.parameters = {}
+        raw_parameters: dict = {}
+        if parameters:
+            if isinstance(parameters, lmfit.Parameters):
+                raw_parameters.update({name: param for name, param in parameters.items()})
+            elif isinstance(parameters, dict):
+                raw_parameters.update(parameters)
+            else:
+                raise DAPError(
+                    f"Invalid parameters type {type(parameters)}. Expected dict or lmfit.Parameters."
+                )
         if amplitude:
-            self.parameters["amplitude"] = amplitude
+            raw_parameters["amplitude"] = amplitude
         if center:
-            self.parameters["center"] = center
+            raw_parameters["center"] = center
         if sigma:
-            self.parameters["sigma"] = sigma
-
-        self.parameters = deserialize_param_object(self.parameters)
+            raw_parameters["sigma"] = sigma
+
+        override_params = deserialize_param_object(raw_parameters)
+        if len(override_params) > 0:
+            valid_names = set(getattr(self.model, "param_names", []))
+            if valid_names:
+                invalid_names = set(override_params.keys()) - valid_names
+                for name in invalid_names:
+                    logger.warning(
+                        f"Ignoring unknown lmfit parameter '{name}' for model '{self.model.__class__.__name__}'."
+                    )
+                    override_params.pop(name, None)
+
+        self._parameter_override_names = list(override_params.keys())
+        if len(override_params) > 0:
+            # If `params=` is provided to lmfit, it must contain ALL parameters.
+            # Start from model defaults and apply overrides on top.
+            full_params = self.model.make_params()
+            for name, override in override_params.items():
+                full_params[name].set(
+                    value=override.value,
+                    vary=override.vary,
+                    min=override.min,
+                    max=override.max,
+                    expr=override.expr,
+                    brute_step=getattr(override, "brute_step", None),
+                )
+            self.parameters = full_params
+            logger.info(
+                f"Configured lmfit model={self.model.__class__.__name__} with override_params={serialize_lmfit_params(override_params)}"
+            )
+        else:
+            self.parameters = None
+            if parameters or amplitude or center or sigma:
+                logger.info(
+                    f"No usable lmfit parameter overrides after validation for model={self.model.__class__.__name__} "
+                    f"(input_keys={list(raw_parameters.keys())})"
+                )
 
         if data_x is not None and data_y is not None:
             self.data = {
@@ -342,9 +388,12 @@ def get_data_from_current_scan(
             "scan_data": True,
         }
 
-    def process(self) -> tuple[dict, dict]:
+    def process(self) -> tuple[dict, dict] | None:
         """
         Process data and return the result.
+
+        Returns:
+            tuple[dict, dict]: Processed data and metadata if successful, None otherwise.
         """
         # get the data
         if not self.data:
@@ -354,10 +403,31 @@ def process(self) -> tuple[dict, dict]:
         y = self.data["y"]
 
         # fit the data
+        model_name = self.model.__class__.__name__
         if self.parameters:
-            result = self.model.fit(y, x=x, params=self.parameters)
+            logger.info(
+                f"Running lmfit fit: model={model_name} points={len(x)} fixed/override_params={self._parameter_override_names}"
+            )
         else:
-            result = self.model.fit(y, x=x)
+            logger.info(f"Running lmfit fit: model={model_name} points={len(x)} params=<default>")
+
+        try:
+            if self.parameters:
+                result = self.model.fit(y, x=x, params=self.parameters)
+            else:
+                result = self.model.fit(y, x=x)
+        except Exception as exc:  # pylint: disable=broad-except
+            if self.parameters is not None:
+                try:
+                    params_str = serialize_lmfit_params(self.parameters)
+                except Exception as ser_exc:
+                    params_str = f"<serialization failed: {ser_exc}>"
+            else:
+                params_str = "<None>"
+            logger.warning(
+                f"lmfit fit failed: model={model_name} points={len(x)} parameters={params_str} error={exc}"
+            )
+            return
 
         # if the fit was only on a subset of the data, add the original x values to the output
         if self.data["x_lim"] or self.oversample != 1:
diff --git a/bec_server/tests/tests_data_processing/test_lmfit1d_service.py b/bec_server/tests/tests_data_processing/test_lmfit1d_service.py
index 9e16ba0cb..ff40bc319 100644
--- a/bec_server/tests/tests_data_processing/test_lmfit1d_service.py
+++ b/bec_server/tests/tests_data_processing/test_lmfit1d_service.py
@@ -161,6 +161,54 @@ def test_LmfitService1D_configure_selected_devices(lmfit_service):
         get_data.assert_called_once()
 
 
+def test_LmfitService1D_configure_accepts_generic_parameters_and_filters_invalid(lmfit_service):
+    x = np.linspace(-1.0, 1.0, 15)
+    y = np.exp(-(x**2))
+    lmfit_service.configure(
+        data_x=x,
+        data_y=y,
+        parameters={"amplitude": {"value": 1.0, "vary": False}, "frequency": {"value": 2.0}},
+    )
+    assert lmfit_service.parameters["amplitude"].value == 1.0
+    assert lmfit_service.parameters["amplitude"].vary is False
+    assert "frequency" not in lmfit_service.parameters
+
+
+def test_LmfitService1D_configure_accepts_lmfit_parameters_object(lmfit_service):
+    x = np.linspace(-1.0, 1.0, 15)
+    y = np.exp(-(x**2))
+    params = lmfit.models.GaussianModel().make_params()
+    params["amplitude"].set(value=1.0, vary=False)
+    lmfit_service.configure(data_x=x, data_y=y, parameters=params)
+    assert lmfit_service.parameters["amplitude"].value == 1.0
+    assert lmfit_service.parameters["amplitude"].vary is False
+
+
+def test_LmfitService1D_configure_invalid_parameters_type_raises(lmfit_service):
+    x = np.linspace(-1.0, 1.0, 15)
+    y = np.exp(-(x**2))
+    with pytest.raises(DAPError):
+        lmfit_service.configure(data_x=x, data_y=y, parameters=["amplitude", 1.0])  # type: ignore[arg-type]
+
+
+def test_LmfitService1D_configure_parameters_work_for_sine_model():
+    if not hasattr(lmfit.models, "SineModel"):
+        pytest.skip("lmfit.models.SineModel not available in this environment")
+    service = LmfitService1D(model="SineModel", continuous=False, client=mock.MagicMock())
+    x = np.linspace(0.0, 2.0 * np.pi, 25)
+    y = np.sin(x)
+    service.configure(
+        data_x=x,
+        data_y=y,
+        parameters={"frequency": {"value": 1.0, "vary": False}, "center": {"value": 0.0}},
+    )
+    assert service.parameters["frequency"].value == 1.0
+    assert service.parameters["frequency"].vary is False
+    assert "center" not in service.parameters
+    assert "amplitude" in service.parameters
+    assert "shift" in service.parameters
+
+
 def test_LmfitService1D_get_model(lmfit_service):
     model = lmfit_service.get_model("GaussianModel")
     assert model.__name__ == "GaussianModel"