diff --git a/app/src/main/java/com/kunfei/bookshelf/help/storage/WebDavHelp.kt b/app/src/main/java/com/kunfei/bookshelf/help/storage/WebDavHelp.kt
index 7cfe32314c..7a21edafbd 100644
--- a/app/src/main/java/com/kunfei/bookshelf/help/storage/WebDavHelp.kt
+++ b/app/src/main/java/com/kunfei/bookshelf/help/storage/WebDavHelp.kt
@@ -1,6 +1,8 @@
 package com.kunfei.bookshelf.help.storage
 
 import android.content.Context
+import android.os.Handler
+import android.os.Looper
 import com.kunfei.bookshelf.MApplication
 import com.kunfei.bookshelf.base.observer.MySingleObserver
 import com.kunfei.bookshelf.constant.AppConstant
@@ -13,6 +15,7 @@ import io.reactivex.SingleOnSubscribe
 import io.reactivex.android.schedulers.AndroidSchedulers
 import io.reactivex.schedulers.Schedulers
 import org.jetbrains.anko.selector
+import org.jetbrains.anko.toast
 import java.io.File
 import java.text.SimpleDateFormat
 import java.util.*
@@ -24,9 +27,11 @@ object WebDavHelp {
         FileHelp.getCachePath()
     }
 
-    private fun getWebDavUrl(): String? {
+    private fun getWebDavUrl(): String {
         var url = MApplication.getConfigPreferences().getString("web_dav_url", AppConstant.DEFAULT_WEB_DAV_URL)
-        if (url.isNullOrBlank()) return null
+        if (url.isNullOrEmpty()) {
+            url = AppConstant.DEFAULT_WEB_DAV_URL
+        }
         if (!url.endsWith("/")) url += "/"
         return url
     }
@@ -45,7 +50,7 @@ object WebDavHelp {
         val url = getWebDavUrl()
         val names = arrayListOf<String>()
         try {
-            if (!url.isNullOrBlank() && initWebDav()) {
+            if (initWebDav()) {
                 var files = WebDav(url + "YueDu/").listFiles()
                 files = files.reversed()
                 for (index: Int in 0 until min(10, files.size)) {
@@ -75,7 +80,7 @@ object WebDavHelp {
 
     private fun restoreWebDav(name: String, callBack: Restore.CallBack?) {
         Single.create(SingleOnSubscribe<Boolean> { e ->
-            getWebDavUrl()?.let {
+            getWebDavUrl().let {
                 val file = WebDav(it + "YueDu/" + name)
                 file.downloadTo(zipFilePath, true)
                 @Suppress("BlockingMethodInNonBlockingContext")
@@ -92,18 +97,24 @@ object WebDavHelp {
     }
 
     fun backUpWebDav(path: String) {
-        if (initWebDav()) {
-            val paths = arrayListOf(*Backup.backupFileNames)
-            for (i in 0 until paths.size) {
-                paths[i] = path + File.separator + paths[i]
+        try {
+            if (initWebDav()) {
+                val paths = arrayListOf(*Backup.backupFileNames)
+                for (i in 0 until paths.size) {
+                    paths[i] = path + File.separator + paths[i]
+                }
+                FileHelp.deleteFile(zipFilePath)
+                if (ZipUtils.zipFiles(paths, zipFilePath)) {
+                    WebDav(getWebDavUrl() + "YueDu").makeAsDir()
+                    val putUrl = getWebDavUrl() + "YueDu/backup" +
+                            SimpleDateFormat("yyyy-MM-dd", Locale.getDefault())
+                                    .format(Date(System.currentTimeMillis())) + ".zip"
+                    WebDav(putUrl).upload(zipFilePath)
+                }
             }
-            FileHelp.deleteFile(zipFilePath)
-            if (ZipUtils.zipFiles(paths, zipFilePath)) {
-                WebDav(getWebDavUrl() + "YueDu").makeAsDir()
-                val putUrl = getWebDavUrl() + "YueDu/backup" +
-                        SimpleDateFormat("yyyy-MM-dd", Locale.getDefault())
-                                .format(Date(System.currentTimeMillis())) + ".zip"
-                WebDav(putUrl).upload(zipFilePath)
+        } catch (e: Exception) {
+            Handler(Looper.getMainLooper()).post {
+                MApplication.getInstance().toast("WebDav\n${e.localizedMessage}")
             }
         }
     }