Can't add products to cart

Hi
Anyone had this issue and solved it like to share how?

I am using V1.3.7 - everything was working fine after move to new server, but today I'm alerted that customer cannot 'add to cart'.

When they try, it displays 'Shopping cart empty' page.

Having tested today, this is true for all products except one -
One product can be added to the cart, but then the 'remove from cart' does not work with this one!

I have not been able to find anything relating to this on the FAQ's or forum and any insights would be much appreciated! :-)

An update to my post above as I have just been back into my site again and now no products will add to cart - this is even stranger to me that such a change could occur since I last viewed, yet have made no changes??

A further update on this situation...
I have been into my site today and the problem seems to have rectified itself!?

Hurray - at least for now!

Whilst it is great that purchases can now be made, as I have changed nothing to cause - or cure the problem I am still in the dark about how this could happen?

Anyone else experienced the same or similar issues?

An insights much appreciated :-)

Thanks