diff --git a/src/components/forms/task/TaskBasicFields.tsx b/src/components/forms/task/TaskBasicFields.tsx
index ca33305..ecab819 100644
--- a/src/components/forms/task/TaskBasicFields.tsx
+++ b/src/components/forms/task/TaskBasicFields.tsx
@@ -3,6 +3,7 @@
 import { Input } from '@/components/ui/Input';
 import { TaskPriority, TaskStatus } from '@/lib/types';
 import { getAllStatuses, getAllPriorities } from '@/lib/status-config';
+import { ensureDate, formatDateForDateTimeInput } from '@/lib/date-utils';
 
 interface TaskBasicFieldsProps {
   title: string;
@@ -109,7 +110,10 @@ export function TaskBasicFields({
       <Input
         label="Date d'échéance"
         type="datetime-local"
-        value={dueDate ? new Date(dueDate.getTime() - dueDate.getTimezoneOffset() * 60000).toISOString().slice(0, 16) : ''}
+        value={(() => {
+          const date = ensureDate(dueDate);
+          return date ? formatDateForDateTimeInput(date) : '';
+        })()}
         onChange={(e) => onDueDateChange(e.target.value ? new Date(e.target.value) : undefined)}
         disabled={loading}
       />
diff --git a/src/lib/date-utils.ts b/src/lib/date-utils.ts
index ff758c4..c951c2f 100644
--- a/src/lib/date-utils.ts
+++ b/src/lib/date-utils.ts
@@ -34,26 +34,28 @@ export function normalizeDate(date: Date): Date {
  * @param date - Date à formater
  * @returns Format YYYY-MM-DD
  */
-export function formatDateForAPI(date: Date): string {
-  if (!isValid(date)) {
+export function formatDateForAPI(date: Date | string): string {
+  const ensuredDate = ensureDate(date);
+  if (!ensuredDate || !isValid(ensuredDate)) {
     throw new Error('Date invalide fournie à formatDateForAPI');
   }
   
-  const year = date.getFullYear();
-  const month = String(date.getMonth() + 1).padStart(2, '0');
-  const day = String(date.getDate()).padStart(2, '0');
+  const year = ensuredDate.getFullYear();
+  const month = String(ensuredDate.getMonth() + 1).padStart(2, '0');
+  const day = String(ensuredDate.getDate()).padStart(2, '0');
   return `${year}-${month}-${day}`;
 }
 
 /**
  * Formate une date pour l'affichage en français
  */
-export function formatDateForDisplay(date: Date, formatType: keyof typeof DATE_FORMATS = 'DISPLAY_MEDIUM'): string {
-  if (!isValid(date)) {
+export function formatDateForDisplay(date: Date | string, formatType: keyof typeof DATE_FORMATS = 'DISPLAY_MEDIUM'): string {
+  const ensuredDate = ensureDate(date);
+  if (!ensuredDate || !isValid(ensuredDate)) {
     throw new Error('Date invalide fournie à formatDateForDisplay');
   }
   
-  return format(date, DATE_FORMATS[formatType], { locale: fr });
+  return format(ensuredDate, DATE_FORMATS[formatType], { locale: fr });
 }
 
 /**
@@ -66,9 +68,14 @@ export function formatDateShort(date: Date): string {
 /**
  * Calcule le nombre de jours écoulés depuis une date
  */
-export function getDaysAgo(date: Date): number {
+export function getDaysAgo(date: Date | string): number {
+  const ensuredDate = ensureDate(date);
+  if (!ensuredDate) {
+    throw new Error('Date invalide fournie à getDaysAgo');
+  }
+  
   const today = getToday();
-  const diffTime = today.getTime() - normalizeDate(date).getTime();
+  const diffTime = today.getTime() - normalizeDate(ensuredDate).getTime();
   return Math.floor(diffTime / (1000 * 60 * 60 * 24));
 }
 
@@ -82,25 +89,36 @@ export function formatDateLong(date: Date): string {
 /**
  * Vérifie si une date est aujourd'hui
  */
-export function isToday(date: Date): boolean {
+export function isToday(date: Date | string): boolean {
+  const ensuredDate = ensureDate(date);
+  if (!ensuredDate) return false;
+  
   const today = new Date();
-  return normalizeDate(date).getTime() === normalizeDate(today).getTime();
+  return normalizeDate(ensuredDate).getTime() === normalizeDate(today).getTime();
 }
 
 /**
  * Vérifie si une date est hier
  */
-export function isYesterday(date: Date): boolean {
+export function isYesterday(date: Date | string): boolean {
+  const ensuredDate = ensureDate(date);
+  if (!ensuredDate) return false;
+  
   const yesterday = new Date();
   yesterday.setDate(yesterday.getDate() - 1);
-  return normalizeDate(date).getTime() === normalizeDate(yesterday).getTime();
+  return normalizeDate(ensuredDate).getTime() === normalizeDate(yesterday).getTime();
 }
 
 /**
  * Compare deux dates (sans tenir compte de l'heure)
  */
-export function isSameDay(date1: Date, date2: Date): boolean {
-  return normalizeDate(date1).getTime() === normalizeDate(date2).getTime();
+export function isSameDay(date1: Date | string, date2: Date | string): boolean {
+  const ensuredDate1 = ensureDate(date1);
+  const ensuredDate2 = ensureDate(date2);
+  
+  if (!ensuredDate1 || !ensuredDate2) return false;
+  
+  return normalizeDate(ensuredDate1).getTime() === normalizeDate(ensuredDate2).getTime();
 }
 
 /**
@@ -258,3 +276,52 @@ export function formatDistanceToNow(date: Date, options?: { addSuffix?: boolean
     addSuffix: options?.addSuffix ?? true
   });
 }
+
+/**
+ * S'assure qu'une valeur est un objet Date valide
+ * Convertit les chaînes de caractères en Date si nécessaire
+ */
+export function ensureDate(value: Date | string | null | undefined): Date | null {
+  if (value === null || value === undefined) {
+    return null;
+  }
+  
+  // Si c'est déjà un objet Date valide
+  if (value instanceof Date && isValid(value)) {
+    return value;
+  }
+  
+  // Si c'est une chaîne de caractères, essayer de la parser
+  if (typeof value === 'string') {
+    try {
+      const parsed = parseDate(value);
+      return parsed;
+    } catch {
+      console.warn(`Impossible de parser la date: ${value}`);
+      return null;
+    }
+  }
+  
+  // Si c'est un objet Date mais invalide, essayer de le recréer
+  if (value instanceof Date) {
+    try {
+      const time = value.getTime();
+      if (!isNaN(time)) {
+        return value;
+      }
+    } catch {
+      console.warn('Objet Date invalide détecté');
+    }
+  }
+  
+  console.warn('Valeur de date non supportée:', value);
+  return null;
+}
+
+/**
+ * S'assure qu'une valeur est un objet Date valide, avec une valeur par défaut
+ */
+export function ensureDateWithDefault(value: Date | string | null | undefined, defaultValue: Date = new Date()): Date {
+  const result = ensureDate(value);
+  return result || defaultValue;
+}