diff --git a/apps/client/src/common/api/apiUtils.ts b/apps/client/src/common/api/apiUtils.ts
index 4042761bb..4388980df 100644
--- a/apps/client/src/common/api/apiUtils.ts
+++ b/apps/client/src/common/api/apiUtils.ts
@@ -11,7 +11,6 @@ export function maybeAxiosError(error: unknown) {
     const statusText = (error as AxiosError).response?.statusText ?? '';
     let data = (error as AxiosError).response?.data ?? '';
     if (typeof data === 'object') {
-      // TODO: use error instead, when migrated
       if ('message' in data) {
         data = JSON.stringify(data.message);
       } else {
diff --git a/apps/client/src/common/hooks/useEventAction.ts b/apps/client/src/common/hooks/useEventAction.ts
index 1cb8af577..7bd9ff7c4 100644
--- a/apps/client/src/common/hooks/useEventAction.ts
+++ b/apps/client/src/common/hooks/useEventAction.ts
@@ -100,7 +100,7 @@ export const useEventAction = () => {
         // @ts-expect-error -- we know that the object is well formed now
         await _addEventMutation.mutateAsync(newEvent);
       } catch (error) {
-        logAxiosError('Error fetching data', error);
+        logAxiosError('Failed adding event', error);
       }
     },
     [_addEventMutation, defaultPublic, queryClient, startTimeIsLastEnd],
diff --git a/apps/server/src/classes/data-provider/DataProvider.ts b/apps/server/src/classes/data-provider/DataProvider.ts
index ea5285b9b..031a537d5 100644
--- a/apps/server/src/classes/data-provider/DataProvider.ts
+++ b/apps/server/src/classes/data-provider/DataProvider.ts
@@ -46,7 +46,6 @@ export class DataProvider {
 
   static async clearRundown() {
     data.rundown = [];
-    // @ts-expect-error -- not sure how to type, this is library side
     await db.write();
   }
 
@@ -100,7 +99,6 @@ export class DataProvider {
   }
 
   static async persist() {
-    // @ts-expect-error -- not sure how to type, this is library side
     await db.write();
   }
 
diff --git a/apps/server/src/controllers/ontimeController.ts b/apps/server/src/controllers/ontimeController.ts
index 76eca8aea..d481e245a 100644
--- a/apps/server/src/controllers/ontimeController.ts
+++ b/apps/server/src/controllers/ontimeController.ts
@@ -149,7 +149,7 @@ export const postAliases = async (req, res) => {
     await DataProvider.setAliases(newAliases);
     res.status(200).send(newAliases);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -172,7 +172,7 @@ export const postUserFields = async (req, res) => {
     await DataProvider.setUserFields(newData);
     res.status(200).send(newData);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -235,7 +235,7 @@ export const postSettings = async (req, res) => {
     await DataProvider.setSettings(newData);
     res.status(200).send(newData);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -270,7 +270,7 @@ export const postViewSettings = async (req, res) => {
     await DataProvider.setViewSettings(newData);
     res.status(200).send(newData);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -298,7 +298,7 @@ export const postOscSubscriptions = async (req, res) => {
 
     res.send(oscSettings).status(200);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -319,7 +319,7 @@ export const postOSC = async (req, res) => {
 
     res.send(oscSettings).status(200);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -348,7 +348,7 @@ export async function patchPartialProjectFile(req, res) {
     }
     res.status(200).send();
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 }
 
@@ -409,6 +409,6 @@ export const postNew: RequestHandler = async (req, res) => {
     await deleteAllEvents();
     res.status(201).send(newData);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
diff --git a/apps/server/src/controllers/playbackController.ts b/apps/server/src/controllers/playbackController.ts
index fe71f19c1..fa1fc80e8 100644
--- a/apps/server/src/controllers/playbackController.ts
+++ b/apps/server/src/controllers/playbackController.ts
@@ -13,14 +13,14 @@ export const pbStart = async (req, res) => {
   const { eventId, eventIndex } = req.query;
   if (eventId) {
     const success = PlaybackService.startById(eventId);
-    success ? res.sendStatus(202) : res.status(400).send('Invalid event ID');
+    success ? res.sendStatus(202) : res.status(400).send({ message: 'Invalid event ID' });
   } else if (eventIndex) {
     const index = Number(eventIndex);
     if (!isNaN(index)) {
       const success = PlaybackService.startByIndex(eventIndex - 1);
-      success ? res.sendStatus(202) : res.status(400).send('Invalid event index');
+      success ? res.sendStatus(202) : res.status(400).send({ message: 'Invalid event index' });
     } else {
-      res.status(400).send('Invalid event index');
+      res.status(400).send({ message: 'Invalid event index' });
     }
   } else {
     PlaybackService.start();
@@ -69,17 +69,17 @@ export const pbLoad = async (req, res) => {
   const { eventId, eventIndex } = req.query;
   if (eventId) {
     const success = PlaybackService.loadById(eventId);
-    success ? res.sendStatus(202) : res.status(400).send('Invalid event ID');
+    success ? res.sendStatus(202) : res.status(400).send({ message: 'Invalid event ID' });
   } else if (eventIndex) {
     const index = Number(eventIndex);
     if (!isNaN(index)) {
       const success = PlaybackService.loadByIndex(eventIndex - 1);
-      success ? res.sendStatus(202) : res.status(400).send('Invalid event index');
+      success ? res.sendStatus(202) : res.status(400).send({ message: 'Invalid event index' });
     } else {
-      res.status(400).send('Invalid event index');
+      res.status(400).send({ message: 'Invalid event index' });
     }
   } else {
-    res.status(400).send('No event given');
+    res.status(400).send({ message: 'No event given' });
   }
 };
 
diff --git a/apps/server/src/controllers/projectController.ts b/apps/server/src/controllers/projectController.ts
index c9f6e8d0e..095cc2702 100644
--- a/apps/server/src/controllers/projectController.ts
+++ b/apps/server/src/controllers/projectController.ts
@@ -30,6 +30,6 @@ export const postProject: RequestHandler = async (req, res) => {
     const newData = await DataProvider.setProjectData(newEvent);
     res.status(200).send(newData);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
diff --git a/apps/server/src/controllers/rundownController.ts b/apps/server/src/controllers/rundownController.ts
index c2a00231a..e0e55e357 100644
--- a/apps/server/src/controllers/rundownController.ts
+++ b/apps/server/src/controllers/rundownController.ts
@@ -29,7 +29,7 @@ export const rundownPost: RequestHandler = async (req, res) => {
     const newEvent = await addEvent(req.body);
     res.status(201).send(newEvent);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -44,7 +44,7 @@ export const rundownPut: RequestHandler = async (req, res) => {
     const event = await editEvent(req.body);
     res.status(200).send(event);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -58,7 +58,7 @@ export const rundownReorder: RequestHandler = async (req, res) => {
     const event = await reorderEvent(eventId, from, to);
     res.status(200).send(event);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -72,7 +72,7 @@ export const rundownSwap: RequestHandler = async (req, res) => {
     await swapEvents(from, to);
     res.sendStatus(200);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -83,7 +83,7 @@ export const rundownApplyDelay: RequestHandler = async (req, res) => {
     await applyDelay(req.params.eventId);
     res.sendStatus(200);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -94,7 +94,7 @@ export const deleteEventById: RequestHandler = async (req, res) => {
     await deleteEvent(req.params.eventId);
     res.sendStatus(204);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
 
@@ -105,6 +105,6 @@ export const rundownDelete: RequestHandler = async (req, res) => {
     await deleteAllEvents();
     res.sendStatus(204);
   } catch (error) {
-    res.status(400).send(error);
+    res.status(400).send({ message: error.toString() });
   }
 };
diff --git a/apps/server/src/modules/loadDb.ts b/apps/server/src/modules/loadDb.ts
index 4b831f131..9442b1228 100644
--- a/apps/server/src/modules/loadDb.ts
+++ b/apps/server/src/modules/loadDb.ts
@@ -67,7 +67,7 @@ async function loadDb() {
   return { db, data };
 }
 
-export let db = {};
+export let db = {} as Low<DatabaseModel>;
 export let data = {} as DatabaseModel;
 export const dbLoadingProcess = loadDb();
 
diff --git a/apps/server/src/services/rundown-service/RundownService.ts b/apps/server/src/services/rundown-service/RundownService.ts
index 8da7f6642..e2efb97d0 100644
--- a/apps/server/src/services/rundown-service/RundownService.ts
+++ b/apps/server/src/services/rundown-service/RundownService.ts
@@ -158,7 +158,7 @@ export function updateTimer(affectedIds?: string[]) {
 export async function addEvent(eventData: Partial<OntimeEvent> | Partial<OntimeDelay> | Partial<OntimeBlock>) {
   const numEvents = DataProvider.getRundownLength();
   if (numEvents > MAX_EVENTS) {
-    throw new Error(`ERROR: Reached limit number of ${MAX_EVENTS} events`);
+    throw new Error(`Reached limit number of ${MAX_EVENTS} events`);
   }
 
   let newEvent: Partial<OntimeBaseEvent> = {};