rail from Montpellier to Barcelona

You should be able to book this route at www.sncf.com. However, when I tried to do a dummy booking a moment ago, I got a "technical difficulties" message. For the price of an international phone call, you can book this route at the Deutsche Bahn Call Centre. Call 011 (international access code for Canada and the US) + 49 (country code for Germany) + 1805 996633.

I was able to log in and get so far but the route and time I was looking for came up that it was not avaialable when I chose it. Rail Europe states that route is not yet for sale. I am looking for the direct train which is only just about 4 hours.
so correct me if I am wrong, if we book on line through them then we HAVE to pick the ticket up at the train station correct?

even when I chose a date that is coming up on rail europe their site is stating I can not book certain routes.
odd

SNCF will only allow you to book 90 days in advance for most trains....120 in advance, I believe, for the Eurostar. Try a dummy date within the 90-day period and see what happens. One of the problems with us booking is that our prime hours....evening....is early morning there, when the site might be down for maintenance, etc.

Is there a reason for needing to book this in advance? You can almost certainly save money by buying the ticket in Montpellier and you won't have to worry about being locked into a specific day/time.

well we actually need to arrive in Barcelona on the given day June 21st.

It appears SNCF has developed a policy of not listing those foreign trains it's not in direct competition with. The two trains/day that take 4 hours are both Spanish...the Talgo and Mare Nostrum trains. The longer journeys are French trains...but they're the only ones you can purchase over the SNCF website. Since purchasing on-line from the Spanish rail website is difficult, I would suggest calling the German rail network at 011-49-1805-996633. It'll cost 12 cents Euro per minute, in addition to your normal long-distance phone charges...but cheaper than RailEurope (which, by the way, seems to list only the SNCF services).

I think that if you are flexible about the train (willing to take either 2nd or first class, willing to take a later or earlier train) you are very likely to find seats that will get you to Barcelona on the 21st, even at the last minute.

For more security, you could buy your tickets (at any train station) the day you arrive in Europe.

Or: You will pay a premium for Rail Europe but perhaps it is worth it for peace of mind.

Good luck!