Enterprise search results - document links not opening files.

I have a crawl running against our SAN and although the documents are searchable, when we click on the link to open them it does nothing..

Documents such as word that are found in any SharePoint sites can be opened by clicking on the link without any problems.

One of our other search sites works fine with documents on the SAN, just this new one that doesn't

I can not find any difference between the two search centres.

Any help or ideas would be appreciated.

Thanks