International settings on Button for file upload

I have a site for a client who has individual pages for each of their clients which they can only see their relevant page once they log in.

This authorised user page has a file share facility in it. This works for all their clients apart from one. This is a Japanese client, and they have a couple of issues.

Firstly they have an issue with uploading a file on the office computer, but OK on a home laptop. I suspect that this may be a security setting on the companies environment, however are their any ways you may suggest that this may be resolved out side of changing the companies security profile.

Second issue is that my client's client says that the "Add file button has disappeared and turned to Japanese button". I assume that this is pulling in profile setting from the PC or network. Do you know of any way to override this.

Actually these issues may be related in that some changes occur to the "Add File button" that prevent the file upload.

( If of use I use the CMS system Mojoportal to develop the site)

Any suggestions would be very helpful in placating my client.