Googlebot webcrawler error

I received an email from google with the following error:

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networkexpress.toastmastersclubs.org/ : Googlebot can't access your site

Over the last 24 hours, Googlebot encountered 1 errors while attempting to access your robots.txt. To ensure that we didn't crawl any pages listed in that file, we postponed our crawl. Your site's overall robots.txt error rate is 100.0%.

You can see more details about these errors in Webmaster Tools.
***

I haven't made any major changes to the site, so I do not know why I'm getting this error now. Also, since toasthost is providing the framework for the site, I don't have visibility to all the files that go into it. Was there some change made to the robots.txt file? I did not see other support requests on this topic so maybe this is just happening with our club.

Any advice on how to resolve this error? If we add or change pages, I want them to be found on google. Thank you,

Cathleen
Network Express, club 2945

Kathleen,

Is this the first time you have ever received this message?

Doing a Google search on "Googlebot can't access your site" shows that is a very infrequent message that can happen if Google cannot locate your site for whatever reason, either on their side or our server side.

What is the time stamp on the email?

I've never seen this message before. Timestamp was Sunday, July 13 at 5:28 PM. It was still giving the error this morning but I just checked it again and it looks like it's spontaneously fixed itself. I don't understand why it stopped working but I had been hoping for some kind of automatic fix. I suppose I won't worry about it unless I receive another email notification.

Cathleen (with a C this time),

Thanks for that information. Maybe Brian or Steve can look at the server log to see if there was an issue around that time frame, but so far, you are the only member that has reported the issue, ever.