FTP and update problems

Hello. I have three problems. These three problems are maybe connected or not, I don’t know.

1. Problem:

I have recently moved my website to another host. Website works fine. I’m having problems when uploading plugins via ftp client. I can upload them successfully, but when I login into my wordpress backoffice and go to the plugins section to active them, I can’t see those plugins that I have uploaded via ftp client. Plugins aren’t there. I can see them in my ftp client but not in the wordpress backoffice plugins section.

I’m hoping anyone has an idea.

2. Problem:

When I’m accessing my website via mobile phone, I can access my website. But it looks like that is pulling up some cached copy from some where, I have no idea where. And I think it has something to do with the wp-super-cache plugin. If I upload this plugin via ftp (obviously I can’t see it in wordpress dashboard), I get some strange warning at the top of the website, when try to access it with my cell phone.

The other thing is that I can’t access any of the other posts on the website with the cell phone (note that there is no problems when accessing it on the computer).

The warning: include()[function include]: Failed opening ‘home/ … /plugins/wp-super-cache/wp-cache-base.php’ for inclusion (include_path=’/user/lib/php:/usr/local/lib/php’) in /…/plugins/wp-super-cache/wp-cache.php on line 53

I get three similiar of those above.

3. Problem

I can’t update wordpress automaticlly or manually. If I try to update it manually I still get that message on the top of the dashboard that says: there is an update available.

I hope you can help me.

Thank you for your help and support.
Mitja