Please check whether the “Indexing external devices after connecting to a computer”(or something like this) option is ticked in the settings of the file manager. Otherwise, I don’t know other solutions of your problem.

Maybe the most useful solution is to backup your files and reinstall the system.😂

thanks for the tip. what do I do with it? I'm not a complete newbie but I need some directions when I'm doing something new

Since I’m poor in English and I don’t have my computer around me,I can only describe the process in Chinese.please translate it in English yourself.

打开文件管理器，点击窗口右上角“最小化”左边的菜单按钮。点击菜单中的“设置”。向下滚动设置页面，在“高级”“索引”的标题下面有一个“自动索引外置磁盘”的选项，请勾选它。

这是正常情况下的解决办法。如果这不起作用，那么它可能是一个比较复杂的问题。

@pzm9012 My file manager - Space FM - doesn't have a setting like that. Which file manager are you using?

just the deepin file manager which is pre-installed in deepin

Your English looks like it's better than my Chinese. 😄

Thanks, I'll do my best to translate it

My problem here might be bigger than I thought. I've followed the suggestions everyone offered. When I click on the external drive I get this message: "To access the disk you must format the disk first. Are you sure you want to format it now?"

But I used this disk in the past and it is already formatted

ntfs

Can you access the disk in the file managers other than deepin file manager,or on other systems or devices?

If not,your disk may have been broken. Normally what I told you to do just now don’t hurt it.

Nope. Can't mount it Space FM either. There I get the ominous message:

"Error mounting /dev/sdb1:

GDBus.Error:org.freedesktop.UDisks2.Error.Failed: Error mounting /dev/sdb1 at /media/jon/TOSHIBA EXT: Unknow error when mounting /dev/sdb1"

That’s an unknown error so I don’t know how to deal with it.You may use some softwares to recover your files in it and format it.

I’m ready to go offline. Here’s a Chinese Deepin discussion Telegram Group (I cannot find the English one)and you can seek for help in it: https://bbs.deepin.org/zh/post/230231