diff --git a/scripts/autoupdate.sh b/scripts/autoupdate.sh
index db1d552..c46e29f 100644
--- a/scripts/autoupdate.sh
+++ b/scripts/autoupdate.sh
@@ -19,13 +19,13 @@ board_id=$(cat /etc/board.json | jsonfilter -e '@["model"].name' | tail -c 4 | t
 mount -t tmpfs -o remount,size=650m tmpfs /tmp
 rm -rf /tmp/upg && mkdir /tmp/upg && cd /tmp/upg
 wget https://ghproxy.com/https://github.com/klever1988/nanopi-openwrt/releases/download/$(date +%Y-%m-%d)/$board_id$ver.img.gz -O $board_id.img.gz || true
-if [ -f $board_id.img.gz ]; then
+if [ $? -eq 0 ]; then
 	wget https://ghproxy.com/https://github.com/klever1988/nanopi-openwrt/releases/download/$(date +%Y-%m-%d)/$board_id$ver.img.md5 -O md5sum.txt
 	echo -e '\e[92m今天固件已下载，准备解压\e[0m'
 else
 	echo -e '\e[91m今天的固件还没更新，尝试下载昨天的固件\e[0m'
 	wget https://ghproxy.com/https://github.com/klever1988/nanopi-openwrt/releases/download/$(date -d "@$(( $(busybox date +%s) - 86400))" +%Y-%m-%d)/$board_id$ver.img.gz -O $board_id.img.gz || true
-	if [ -f $board_id.img.gz ]; then
+	if [ $? -eq 0 ]; then
 		wget https://ghproxy.com/https://github.com/klever1988/nanopi-openwrt/releases/download/$(date -d "@$(( $(busybox date +%s) - 86400))" +%Y-%m-%d)/$board_id$ver.img.md5 -O md5sum.txt
 		echo -e '\e[92m昨天的固件已下载，准备解压\e[0m'
 	else