diff --git a/app/src/main/java/io/legado/app/model/remote/RemoteBookWebDav.kt b/app/src/main/java/io/legado/app/model/remote/RemoteBookWebDav.kt
index 35bc537ef..ed7ae2612 100644
--- a/app/src/main/java/io/legado/app/model/remote/RemoteBookWebDav.kt
+++ b/app/src/main/java/io/legado/app/model/remote/RemoteBookWebDav.kt
@@ -6,6 +6,7 @@ import io.legado.app.constant.BookType
 import io.legado.app.data.entities.Book
 import io.legado.app.exception.NoStackTraceException
 import io.legado.app.help.AppWebDav
+import io.legado.app.help.config.AppConfig
 import io.legado.app.lib.webdav.WebDav
 import io.legado.app.lib.webdav.WebDavFile
 import io.legado.app.model.localBook.LocalBook
@@ -58,6 +59,8 @@ object RemoteBookWebDav : RemoteBookManager() {
     }
 
     override suspend fun downloadRemoteBook(remoteBook: RemoteBook): Uri {
+        AppConfig.defaultBookTreeUri
+            ?: throw NoStackTraceException("没有设置书籍保存位置!")
         return AppWebDav.authorization?.let {
             val webdav = WebDav(remoteBook.path, it)
             webdav.downloadInputStream().let { inputStream ->
@@ -90,4 +93,4 @@ object RemoteBookWebDav : RemoteBookManager() {
         } ?: throw NoStackTraceException("webDav没有配置")
     }
 
-}
\ No newline at end of file
+}