diff --git a/pom.xml b/pom.xml
index e3d74a3..af075c3 100644
--- a/pom.xml
+++ b/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>net.lamgc</groupId>
     <artifactId>ContentGrabbingJi</artifactId>
-    <version>2.5.2-20200520.1-SNAPSHOT</version>
+    <version>2.5.2-20200522.1-SNAPSHOT</version>
 
     <repositories>
         <repository>
diff --git a/src/main/java/net/lamgc/cgj/bot/BotCommandProcess.java b/src/main/java/net/lamgc/cgj/bot/BotCommandProcess.java
index 559e3a8..84a90f3 100644
--- a/src/main/java/net/lamgc/cgj/bot/BotCommandProcess.java
+++ b/src/main/java/net/lamgc/cgj/bot/BotCommandProcess.java
@@ -29,6 +29,7 @@ import org.slf4j.LoggerFactory;
 import java.io.File;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
 import java.text.SimpleDateFormat;
 import java.util.*;
 import java.util.concurrent.atomic.AtomicInteger;
@@ -148,7 +149,7 @@ public class BotCommandProcess {
     @Command(commandName = "info")
     public static String artworkInfo(@Argument(name = "$fromGroup") long fromGroup, @Argument(name = "id") int illustId) {
         if(illustId <= 0) {
-            return "错误的作品id！";
+            return "这个作品Id是错误的！";
         }
 
         try {
@@ -708,13 +709,6 @@ public class BotCommandProcess {
         return reportStore.exists(String.valueOf(illustId));
     }
 
-    /*
-    下一目标：
-    添加定时发图
-    定时发图支持设置关注标签
-    标签....标签支持搜索吧
-     */
-
     /**
      * 检查指定作品是否为r18
      * @param illustId 作品Id
@@ -722,13 +716,22 @@ public class BotCommandProcess {
      * @param returnRaw 是否返回原始值
      * @return 如果为true, 则不为全年龄
      * @throws IOException 获取数据时发生异常时抛出
+     * @throws NoSuchElementException 当作品不存在时抛出
      */
-    public static boolean isNoSafe(int illustId, Properties settingProp, boolean returnRaw) throws IOException {
+    public static boolean isNoSafe(int illustId, Properties settingProp, boolean returnRaw) throws IOException, NoSuchElementException {
         boolean rawValue = getIllustInfo(illustId, false).getAsJsonArray("tags").contains(new JsonPrimitive("R-18"));
         return returnRaw || settingProp == null ? rawValue : rawValue && !settingProp.getProperty("image.allowR18", "false").equalsIgnoreCase("true");
     }
 
-    private static JsonObject getIllustInfo(int illustId, boolean flushCache) throws IOException {
+    /**
+     * 获取作品信息
+     * @param illustId 作品Id
+     * @param flushCache 强制刷新缓存
+     * @return 返回作品信息
+     * @throws IOException 当Http请求发生异常时抛出
+     * @throws NoSuchElementException 当作品未找到时抛出
+     */
+    private static JsonObject getIllustInfo(int illustId, boolean flushCache) throws IOException, NoSuchElementException {
         String illustIdStr = buildSyncKey(Integer.toString(illustId));
         JsonObject illustInfoObj = null;
         if (!illustInfoCache.exists(illustIdStr) || flushCache) {
@@ -809,11 +812,19 @@ public class BotCommandProcess {
         }
         return result;
     }
-    
+
+    /**
+     * 获取图片存储目录.
+     * <p>每次调用都会检查目录是否存在, 如不存在则会抛出异常</p>
+     * @return 返回File对象
+     * @throws RuntimeException 当目录创建失败时将包装{@link IOException}异常并抛出.
+     */
     private static File getImageStoreDir() {
-        if(!imageStoreDir.exists() && !imageStoreDir.mkdirs()) {
-            log.warn("酷Q图片缓存目录失效！(Path: {} )", imageStoreDir.getAbsolutePath());
-            throw new RuntimeException(new IOException("文件夹创建失败!"));
+        if(!imageStoreDir.exists() && !Files.isSymbolicLink(imageStoreDir.toPath())) {
+            if(!imageStoreDir.mkdirs()) {
+                log.warn("酷Q图片缓存目录失效！(Path: {} )", imageStoreDir.getAbsolutePath());
+                throw new RuntimeException(new IOException("文件夹创建失败!"));
+            }
         }
         return imageStoreDir;
     }
diff --git a/src/main/java/net/lamgc/cgj/bot/RankingUpdateTimer.java b/src/main/java/net/lamgc/cgj/bot/RankingUpdateTimer.java
index 0f35faf..1f02550 100644
--- a/src/main/java/net/lamgc/cgj/bot/RankingUpdateTimer.java
+++ b/src/main/java/net/lamgc/cgj/bot/RankingUpdateTimer.java
@@ -27,8 +27,9 @@ public class RankingUpdateTimer {
         Calendar cal = Calendar.getInstance();
         cal.setTime(firstRunDate == null ? new Date() : firstRunDate);
         LocalDate currentLocalDate = LocalDate.now();
-        if(cal.get(Calendar.DAY_OF_YEAR) <= currentLocalDate.getDayOfYear() &&
-                cal.get(Calendar.HOUR_OF_DAY) >= 11 && cal.get(Calendar.MINUTE) >= 30) {
+        if(cal.get(Calendar.DAY_OF_YEAR) < currentLocalDate.getDayOfYear() || (
+                cal.get(Calendar.DAY_OF_YEAR) == currentLocalDate.getDayOfYear() &&
+                        (cal.get(Calendar.HOUR_OF_DAY) * 60 + cal.get(Calendar.MINUTE) >= 690))) {
             cal.set(Calendar.DAY_OF_YEAR, currentLocalDate.getDayOfYear() + 1);
         }
         cal.set(Calendar.HOUR_OF_DAY, 11);
@@ -36,7 +37,7 @@ public class RankingUpdateTimer {
         cal.set(Calendar.SECOND, 0);
         cal.set(Calendar.MILLISECOND, 0);
 
-        long delay = cal.getTime().getTime() - (System.currentTimeMillis());
+        long delay = cal.getTime().getTime() - System.currentTimeMillis();
         log.warn("已设置排行榜定时更新, 首次运行时间: {} ({}min)", cal.getTime(), delay / 1000 / 60);
         timer.schedule(new TimerTask() {
             @Override
diff --git a/src/main/java/net/lamgc/cgj/bot/event/BotEventHandler.java b/src/main/java/net/lamgc/cgj/bot/event/BotEventHandler.java
index 26b7583..2533d0c 100644
--- a/src/main/java/net/lamgc/cgj/bot/event/BotEventHandler.java
+++ b/src/main/java/net/lamgc/cgj/bot/event/BotEventHandler.java
@@ -215,12 +215,17 @@ public class BotEventHandler implements EventHandler {
         } catch(ParameterNoFoundException e) {
             result = "命令缺少参数: " + e.getParameterName();
         } catch(DeveloperRunnerException e) {
-            if (!(e.getCause() instanceof InterruptedException)) {
-                log.error("执行命令时发生异常", e);
-                result = "色图姬在执行命令时遇到了一个错误！";
-            } else {
+            Throwable cause = e.getCause();
+            if (cause instanceof InterruptedException) {
                 log.error("命令执行超时, 终止执行.");
                 result = "色图姬发现这个命令的处理时间太久了！所以打断了这个命令。";
+            } else if(cause instanceof NoSuchElementException && cause.getMessage().startsWith("No work found: ")) {
+                String message = cause.getMessage();
+                log.error("指定作品不存在.(Id: {})", message.substring(message.lastIndexOf(": ") + 2));
+                result = "色图姬找不到这个作品！";
+            } else {
+                log.error("执行命令时发生异常", e);
+                result = "色图姬在执行命令时遇到了一个错误！";
             }
         }
         long processTime = System.currentTimeMillis() - time;
diff --git a/src/main/java/net/lamgc/cgj/pixiv/PixivDownload.java b/src/main/java/net/lamgc/cgj/pixiv/PixivDownload.java
index 21ebe55..8846d5a 100644
--- a/src/main/java/net/lamgc/cgj/pixiv/PixivDownload.java
+++ b/src/main/java/net/lamgc/cgj/pixiv/PixivDownload.java
@@ -542,8 +542,9 @@ public class PixivDownload {
      *       }
      *      </pre>
      * @throws IOException 当请求发生异常, 或接口返回错误信息时抛出.
+     * @throws NoSuchElementException 当该作品不存在时抛出异常
      */
-    public JsonObject getIllustInfoByIllustId(int illustId) throws IOException {
+    public JsonObject getIllustInfoByIllustId(int illustId) throws IOException, NoSuchElementException {
         HttpGet request = createHttpGetRequest(PixivURL.getPixivIllustInfoAPI(illustId));
         HttpResponse response = httpClient.execute(request);
         String responseStr = EntityUtils.toString(response.getEntity());
@@ -558,7 +559,7 @@ public class PixivDownload {
         if(illustsArray.size() == 1) {
             return illustsArray.get(0).getAsJsonObject();
         } else {
-            return null;
+            throw new NoSuchElementException("No work found: " + illustId);
         }
     }