diff --git a/src/TickerQ.Caching.StackExchangeRedis/Infrastructure/TickerRedisPersistenceProvider.cs b/src/TickerQ.Caching.StackExchangeRedis/Infrastructure/TickerRedisPersistenceProvider.cs
index a44b6202..da2aa64f 100644
--- a/src/TickerQ.Caching.StackExchangeRedis/Infrastructure/TickerRedisPersistenceProvider.cs
+++ b/src/TickerQ.Caching.StackExchangeRedis/Infrastructure/TickerRedisPersistenceProvider.cs
@@ -339,9 +339,13 @@ public async Task MigrateDefinedCronTickers((string Function, string Expression)
     {
         var now = _clock.UtcNow;
         const string seedPrefix = "MemoryTicker_Seeded_";
-        var functions = cronTickers.Select(x => x.Function).ToHashSet(StringComparer.Ordinal);
 
-        // Load existing seeded cron tickers
+        // Build the complete set of registered function names to detect orphaned tickers.
+        // This covers functions whose InitIdentifier was cleared by a dashboard edit (#517).
+        var allRegisteredFunctions = TickerFunctionProvider.TickerFunctions.Keys
+            .ToHashSet(StringComparer.Ordinal);
+
+        // Load all existing cron tickers
         var existingIds = await _db.SetMembersAsync(CronIdsKey).ConfigureAwait(false);
         var existingList = new List<TCronTicker>();
         foreach (var redisValue in existingIds)
@@ -352,17 +356,22 @@ public async Task MigrateDefinedCronTickers((string Function, string Expression)
             if (cron != null) existingList.Add(cron);
         }
 
-        var seededCron = existingList.Where(c => c.InitIdentifier != null && c.InitIdentifier.StartsWith(seedPrefix)).ToList();
-        var seededToDelete = seededCron.Where(c => !functions.Contains(c.Function)).Select(c => c.Id).ToArray();
+        // Delete all cron tickers whose function no longer exists in the code definitions
+        var orphanedToDelete = existingList
+            .Where(c => !allRegisteredFunctions.Contains(c.Function))
+            .Select(c => c.Id).ToArray();
 
-        foreach (var id in seededToDelete)
+        foreach (var id in orphanedToDelete)
         {
             await RemoveCronIndexesAsync(id).ConfigureAwait(false);
             await RemoveCronOccurrenceIndexesAsyncForCron(id).ConfigureAwait(false);
             await _db.KeyDeleteAsync(CronKey(id)).ConfigureAwait(false);
         }
 
-        var existingByFunction = existingList.ToDictionary(c => c.Function, c => c, StringComparer.Ordinal);
+        var orphanedSet = orphanedToDelete.ToHashSet();
+        var existingByFunction = existingList
+            .Where(c => !orphanedSet.Contains(c.Id))
+            .ToDictionary(c => c.Function, c => c, StringComparer.Ordinal);
         foreach (var (function, expression) in cronTickers)
         {
             if (existingByFunction.TryGetValue(function, out var cron))
diff --git a/src/TickerQ.EntityFrameworkCore/Infrastructure/BasePersistenceProvider.cs b/src/TickerQ.EntityFrameworkCore/Infrastructure/BasePersistenceProvider.cs
index 7348b322..d75906b7 100644
--- a/src/TickerQ.EntityFrameworkCore/Infrastructure/BasePersistenceProvider.cs
+++ b/src/TickerQ.EntityFrameworkCore/Infrastructure/BasePersistenceProvider.cs
@@ -248,36 +248,36 @@ public async Task MigrateDefinedCronTickers((string Function, string Expression)
         var functions = cronTickers.Select(x => x.Function).ToArray();
         var cronSet = dbContext.Set<TCronTicker>();
 
-        // Identify seeded cron tickers (created from in-memory definitions)
-        const string seedPrefix = "MemoryTicker_Seeded_";
-
-        var seededCron = await cronSet
-            .Where(c => c.InitIdentifier != null && c.InitIdentifier.StartsWith(seedPrefix))
-            .ToListAsync(cancellationToken)
-            .ConfigureAwait(false);
-
-        var newFunctionSet = functions.ToHashSet(StringComparer.Ordinal);
-
-        // Delete seeded cron tickers whose function no longer exists in the code definitions
-        var seededToDelete = seededCron
-            .Where(c => !newFunctionSet.Contains(c.Function))
+        // Build the complete set of registered function names to detect orphaned tickers.
+        // This covers functions whose InitIdentifier was cleared by a dashboard edit (#517).
+        var allRegisteredFunctions = TickerFunctionProvider.TickerFunctions.Keys
+            .ToHashSet(StringComparer.Ordinal);
+
+        // Find all cron tickers whose function no longer exists in the code definitions.
+        // This includes seeded tickers (InitIdentifier = "MemoryTicker_Seeded_*") as well as
+        // previously-seeded tickers whose InitIdentifier was cleared by a dashboard update.
+        var orphanedCron = await cronSet
+            .Where(c => !allRegisteredFunctions.Contains(c.Function))
             .Select(c => c.Id)
-            .ToArray();
+            .ToArrayAsync(cancellationToken)
+            .ConfigureAwait(false);
 
-        if (seededToDelete.Length > 0)
+        if (orphanedCron.Length > 0)
         {
             // Delete related occurrences first (if any), then the cron tickers
             await dbContext.Set<CronTickerOccurrenceEntity<TCronTicker>>()
-                .Where(o => seededToDelete.Contains(o.CronTickerId))
+                .Where(o => orphanedCron.Contains(o.CronTickerId))
                 .ExecuteDeleteAsync(cancellationToken)
                 .ConfigureAwait(false);
 
             await cronSet
-                .Where(c => seededToDelete.Contains(c.Id))
+                .Where(c => orphanedCron.Contains(c.Id))
                 .ExecuteDeleteAsync(cancellationToken)
                 .ConfigureAwait(false);
         }
 
+        var newFunctionSet = functions.ToHashSet(StringComparer.Ordinal);
+
         // Load existing (remaining) cron tickers for the current function set
         var existing = await cronSet
             .Where(c => functions.Contains(c.Function))
diff --git a/src/TickerQ/Src/Provider/TickerInMemoryPersistenceProvider.cs b/src/TickerQ/Src/Provider/TickerInMemoryPersistenceProvider.cs
index 64792382..410f8462 100644
--- a/src/TickerQ/Src/Provider/TickerInMemoryPersistenceProvider.cs
+++ b/src/TickerQ/Src/Provider/TickerInMemoryPersistenceProvider.cs
@@ -521,6 +521,17 @@ public Task MigrateDefinedCronTickers((string Function, string Expression)[] cro
         {
             var now = _clock.UtcNow;
 
+            // Remove orphaned cron tickers whose function no longer exists in the code definitions (#517).
+            var allRegisteredFunctions = TickerFunctionProvider.TickerFunctions.Keys
+                .ToHashSet(StringComparer.Ordinal);
+
+            var snapshot = CronTickers.ToArray();
+            foreach (var (id, ticker) in snapshot)
+            {
+                if (!allRegisteredFunctions.Contains(ticker.Function))
+                    CronTickers.TryRemove(id, out _);
+            }
+
             foreach (var (function, expression) in cronTickers)
             {
                 // Check if already exists (take snapshot for thread safety)
@@ -538,7 +549,7 @@ public Task MigrateDefinedCronTickers((string Function, string Expression)[] cro
                         UpdatedAt = now,
                         Request = Array.Empty<byte>()
                     };
-                    
+
                     CronTickers.TryAdd(id, cronTicker);
                 }
             }
diff --git a/src/TickerQ/Src/TickerExecutionTaskHandler.cs b/src/TickerQ/Src/TickerExecutionTaskHandler.cs
index 534e8713..f3a0b950 100644
--- a/src/TickerQ/Src/TickerExecutionTaskHandler.cs
+++ b/src/TickerQ/Src/TickerExecutionTaskHandler.cs
@@ -183,6 +183,11 @@ private async Task RunContextFunctionAsync(InternalFunctionContext context, bool
 
                 stopWatch.Start();
 
+                if (context.CachedDelegate is null)
+                    throw new InvalidOperationException(
+                        $"Ticker function '{context.FunctionName}' was not found in the registered functions. " +
+                        "Ensure the function is properly decorated with [TickerFunction] attribute and the containing class is registered.");
+
                 // Create service scope - will be disposed automatically via await using
                 await using var scope = _serviceProvider.CreateAsyncScope();
                 tickerFunctionContext.SetServiceScope(scope);