My homepage doestn't work after clearing the cache

First I moved one folder(05.qtwz) from (user/pages/03.share), to the root folder(/user/pages). Then, I couldn't visit the homepage after the movement.

But when I deleted the folder(05.qtwz) ， the homepage appears and works again.

As I don't sure what's the problem, I login the admin pannel and clear the cache.

But after that(cache clear), my homepage doestn't work again,

Don't know how to do now next, and the admin pannel still could login in.

Any suggestions for the above situation will be appreciated.

And now when visit my homepage, check the view-source, nothing found. only a blank page.

I finally found that I have changed the page module to the External , but not input the url. and thus may cause the problem. After I input the url or use other page as homepage, I could visit my site again.

So after deleting 05.qtwz and clearing cache, it didn't load? Or did you restore 05.qtwz? What's the header of the MD file in 05.qtwz?

title: 'Cyber Space'

I do it by a baota panel, website:bt.cn

And some error for information as follows:
Twig \ Error \ RuntimeError
An exception has been thrown during the rendering of a template (“The Process class relies on proc_open, which is not available on your PHP installation.”).
Previous exceptions
The Process class relies on proc_open, which is not available on your PHP installation. (0)