diff --git a/apps/web/src/app/main/community/freeboard/[freeboardId]/ClientPage.tsx b/apps/web/src/app/main/community/freeboard/[freeboardId]/ClientPage.tsx
index 0012455d..8028293e 100644
--- a/apps/web/src/app/main/community/freeboard/[freeboardId]/ClientPage.tsx
+++ b/apps/web/src/app/main/community/freeboard/[freeboardId]/ClientPage.tsx
@@ -7,6 +7,8 @@ import CommentInput from './components/CommentInput';
 import FreeboardDetailSkeleton from './components/FreeboardDetailSkeleton';
 import { useGetFreeboardPost } from '@/generated/api/endpoints/freeboard/freeboard';
 import { useAuthRestore } from '@/hooks/useAuth';
+import ErrorFallback from '@/components/ErrorFallback';
+import { ErrorBoundary } from 'react-error-boundary';
 
 /**
  * 자유 게시판 게시글 상세 클라이언트 화면
@@ -18,6 +20,7 @@ export default function ClientPage({ postId }: { postId: number }) {
     data: post,
     isPending,
     error,
+    refetch,
   } = useGetFreeboardPost(postId, {
     query: {
       staleTime: 0, // 언제나 신선하지 않은 것으로 간주
@@ -28,11 +31,37 @@ export default function ClientPage({ postId }: { postId: number }) {
     },
   });
 
-  // TODO: 로딩/에러 처리 구체화 필요
-  // postId가 유효하지 않은 경우 처리 필요
   if (!postId) return <FreeboardDetailSkeleton />;
   if (isPending) return <FreeboardDetailSkeleton />;
-  if (error || !post) return <div>에러가 발생했습니다.</div>;
+  if (error || !post) {
+    return (
+      <main className="space-y-6 pt-12">
+        <Header className="fixed top-0 left-0 right-0 z-50 bg-white">
+          <Header.Left>
+            <Header.BackButton /> {/* router.back() 내부 처리 */}
+          </Header.Left>
+          <Header.Center>자유게시판</Header.Center>
+          <Header.Right>
+            {/* TODO: onClick 핸들러 추가 */}
+            <Header.MenuButton
+              onClick={() => {
+                /* 바텀시트 열기 */
+              }}
+            />
+          </Header.Right>
+        </Header>
+
+        <div className="px-5 pt-16">
+          <ErrorFallback
+            message="게시글을 불러오는 중 오류가 발생했습니다."
+            onRetry={() => {
+              refetch();
+            }}
+          />
+        </div>
+      </main>
+    );
+  }
 
   return (
     <main className="space-y-6 pt-12">
@@ -51,7 +80,16 @@ export default function ClientPage({ postId }: { postId: number }) {
         </Header.Right>
       </Header>
 
-      <FreeboardDetail post={post} />
+      <ErrorBoundary
+        FallbackComponent={({ error, resetErrorBoundary }) => (
+          <ErrorFallback
+            message={error?.message}
+            onRetry={resetErrorBoundary}
+          />
+        )}
+      >
+        <FreeboardDetail post={post} />
+      </ErrorBoundary>
 
       <section className="px-5 pb-6">
         <CommentList
diff --git a/apps/web/src/app/main/community/freeboard/[freeboardId]/components/CommentList.tsx b/apps/web/src/app/main/community/freeboard/[freeboardId]/components/CommentList.tsx
index 1698db26..e8ec2ee4 100644
--- a/apps/web/src/app/main/community/freeboard/[freeboardId]/components/CommentList.tsx
+++ b/apps/web/src/app/main/community/freeboard/[freeboardId]/components/CommentList.tsx
@@ -58,12 +58,12 @@ export default function CommentList({
     );
   }, [data]);
 
-  const latestTotal =
+  const firstPageTotal =
     data?.pages && data.pages.length > 0
-      ? data.pages[data.pages.length - 1]?.total
+      ? data.pages[0]?.total
       : undefined;
 
-  const headerCount = latestTotal ?? initialCount ?? comments.length;
+  const headerCount = firstPageTotal ?? initialCount ?? 0;
 
   return (
     <section aria-label="댓글 섹션" className="flex-1">
diff --git a/apps/web/src/app/main/community/freeboard/[freeboardId]/components/LikeButtonComment.tsx b/apps/web/src/app/main/community/freeboard/[freeboardId]/components/LikeButtonComment.tsx
index 1e348383..42dd6b8d 100644
--- a/apps/web/src/app/main/community/freeboard/[freeboardId]/components/LikeButtonComment.tsx
+++ b/apps/web/src/app/main/community/freeboard/[freeboardId]/components/LikeButtonComment.tsx
@@ -3,11 +3,12 @@
 import { useEffect, useState } from 'react';
 import { ThumbsUp } from 'lucide-react';
 import { useQueryClient } from '@tanstack/react-query';
-import { useAuthGuard, useAuthRestore } from '@/hooks/useAuth';
+import { useAuthGuard } from '@/hooks/useAuth';
 import { useToast } from '@/hooks/ui/useToast';
 import { formatCappedCount } from '@/utils/formatCount';
 import { getGetFreeboardCommentsByCursorQueryKey } from '@/generated/api/endpoints/freeboard-comment/freeboard-comment';
 import { useToggleFreeboardCommentLike } from '@/generated/api/endpoints/freeboard-comment-like/freeboard-comment-like';
+import { clampCount } from '@/utils/clampCount';
 
 interface LikeButtonCommentProps {
   postId: number;
@@ -16,9 +17,6 @@ interface LikeButtonCommentProps {
   initialLikeCount: number;
 }
 
-// 음수 방지(보정) 헬퍼
-const clampMin0 = (n: number) => (n < 0 ? 0 : n);
-
 /**
  * 댓글 좋아요 버튼
  *
@@ -32,7 +30,6 @@ export default function LikeButtonComment({
   initialLiked,
   initialLikeCount,
 }: LikeButtonCommentProps) {
-  const { isRestoring, isAuthenticated } = useAuthRestore();
   const queryClient = useQueryClient();
   const toast = useToast();
   const { guard } = useAuthGuard();
@@ -66,7 +63,7 @@ export default function LikeButtonComment({
         setLiked((prev) => {
           const next = !prev;
           const delta = next ? 1 : -1;
-          setLikeCount((count) => clampMin0(count + delta));
+          setLikeCount((count) => clampCount(count + delta));
           return next;
         });
 
@@ -104,23 +101,6 @@ export default function LikeButtonComment({
       toggleLike.mutate({ freeboardId: postId, commentId });
     });
 
-  // 인증 복원 중임을 명시(시각적 피드백)
-  if (isRestoring) {
-    return (
-      <button
-        className="flex items-center gap-1.5 opacity-60 cursor-wait"
-        disabled
-        aria-label="좋아요 로딩 중"
-        type="button"
-      >
-        <ThumbsUp className="inline w-4 h-4 text-neutral-200" />
-        <span className="text-neutral-500 text-input2">
-          {likeCount}
-        </span>
-      </button>
-    );
-  }
-
   return (
     <button
       type="button"
@@ -129,7 +109,6 @@ export default function LikeButtonComment({
       className="flex items-center gap-1.5"
       disabled={toggleLike.isPending}
       aria-label={liked ? '좋아요 취소' : '좋아요'}
-      title={!isAuthenticated ? '로그인이 필요합니다' : undefined}
     >
       <ThumbsUp
         className={`inline w-4 h-4 text-neutral-200 transition-colors ${
diff --git a/apps/web/src/app/main/community/freeboard/[freeboardId]/components/LikeButtonPost.tsx b/apps/web/src/app/main/community/freeboard/[freeboardId]/components/LikeButtonPost.tsx
index b4b8541c..d3c66d5a 100644
--- a/apps/web/src/app/main/community/freeboard/[freeboardId]/components/LikeButtonPost.tsx
+++ b/apps/web/src/app/main/community/freeboard/[freeboardId]/components/LikeButtonPost.tsx
@@ -3,12 +3,13 @@
 import { useEffect, useState } from 'react';
 import { Heart } from 'lucide-react';
 import { useQueryClient } from '@tanstack/react-query';
-import { useAuthGuard, useAuthRestore } from '@/hooks/useAuth';
+import { useAuthGuard } from '@/hooks/useAuth';
 import { formatCappedCount } from '@/utils/formatCount';
 import { useToast } from '@/hooks/ui/useToast';
 import { FreeboardDetailResponse } from '@/generated/api/models';
 import { getGetFreeboardPostQueryKey } from '@/generated/api/endpoints/freeboard/freeboard';
 import { useToggleFreeboardLike } from '@/generated/api/endpoints/freeboard-like/freeboard-like';
+import { clampCount } from '@/utils/clampCount';
 
 interface LikeButtonPostProps {
   postId: number;
@@ -16,9 +17,6 @@ interface LikeButtonPostProps {
   initialLikeCount: number;
 }
 
-// 음수 방지(보정) 헬퍼
-const clampMin0 = (n: number) => (n < 0 ? 0 : n);
-
 /**
  * 게시글 좋아요 버튼
  *
@@ -31,7 +29,6 @@ export default function LikeButtonPost({
   initialLiked,
   initialLikeCount,
 }: LikeButtonPostProps) {
-  const { isRestoring } = useAuthRestore();
   const queryClient = useQueryClient();
   const toast = useToast();
   const { guard } = useAuthGuard();
@@ -69,7 +66,7 @@ export default function LikeButtonPost({
         setLiked((prev) => {
           const next = !prev;
           const delta = next ? 1 : -1;
-          setLikeCount((count) => clampMin0(count + delta));
+          setLikeCount((count) => clampCount(count + delta));
           return next;
         });
 
@@ -79,7 +76,7 @@ export default function LikeButtonPost({
           (old) => {
             if (!old) return old;
             const nextLiked = !(old.isLiked ?? false);
-            const nextCount = clampMin0(
+            const nextCount = clampCount(
               old.likeCount + (nextLiked ? 1 : -1),
             );
             return {
@@ -125,22 +122,6 @@ export default function LikeButtonPost({
       toggleLike.mutate({ freeboardId: postId });
     });
 
-  // 인증 복원 중임을 명시(시각적 피드백)
-  if (isRestoring) {
-    return (
-      <button
-        className="flex items-center gap-1.5 opacity-60 cursor-wait"
-        disabled
-        aria-label="좋아요 로딩 중"
-      >
-        <Heart className="inline w-4 h-4 text-neutral-200" />
-        <span className="text-neutral-500 text-input2">
-          {formatCappedCount(likeCount)}
-        </span>
-      </button>
-    );
-  }
-
   return (
     <button
       type="button"
diff --git a/apps/web/src/app/main/community/freeboard/[freeboardId]/page.tsx b/apps/web/src/app/main/community/freeboard/[freeboardId]/page.tsx
index fa342bdd..d571ad84 100644
--- a/apps/web/src/app/main/community/freeboard/[freeboardId]/page.tsx
+++ b/apps/web/src/app/main/community/freeboard/[freeboardId]/page.tsx
@@ -31,9 +31,15 @@ export default async function Page({
     const queryOptions = getGetFreeboardPostQueryOptions(postId);
     await queryClient.fetchQuery(queryOptions);
   } catch (error: unknown) {
-    if (isAxiosError(error) && error.response?.status === 404)
-      notFound();
-    return <FreeboardDetailSkeleton />;
+    if (isAxiosError(error)) {
+      const status = error.response?.status;
+
+      if (status === 404) {
+        notFound();
+      }
+    }
+
+    throw error;
   }
 
   const dehydratedState = dehydrate(queryClient);
diff --git a/apps/web/src/components/ErrorFallback.tsx b/apps/web/src/components/ErrorFallback.tsx
index bdbcc9b5..17f527c7 100644
--- a/apps/web/src/components/ErrorFallback.tsx
+++ b/apps/web/src/components/ErrorFallback.tsx
@@ -13,7 +13,7 @@ export default function ErrorFallback({
   onRetry,
 }: ErrorFallbackProps) {
   return (
-    <div className="p-6 text-center space-y-4">
+    <div className="p-12 text-center space-y-4">
       <p className="text-red-500 font-medium">
         {message ?? '문제가 발생했습니다.'}
       </p>
diff --git a/apps/web/src/components/infiniteScrolls/VirtualList.tsx b/apps/web/src/components/infiniteScrolls/VirtualList.tsx
index 72cf5c96..d59f823d 100644
--- a/apps/web/src/components/infiniteScrolls/VirtualList.tsx
+++ b/apps/web/src/components/infiniteScrolls/VirtualList.tsx
@@ -151,7 +151,7 @@ export function VirtualList<T>({
         <div
           key={row.key}
           ref={virtualizer.measureElement}
-          data-index={row.index} // ✅ 경고 해결: 측정 요소에 data-index 추가
+          data-index={row.index}
           style={{
             position: 'absolute',
             top: 0,
diff --git a/apps/web/src/utils/clampCount.ts b/apps/web/src/utils/clampCount.ts
new file mode 100644
index 00000000..76aedb74
--- /dev/null
+++ b/apps/web/src/utils/clampCount.ts
@@ -0,0 +1,6 @@
+/**
+ * 카운트 값이 min(기본 0) 아래로 내려가지 않도록 보정합니다.
+ */
+export const clampCount = (n: number, min = 0) => {
+  return Math.max(n, min);
+};