Groups Not Showing

I hope I haven't duplicated a thread here but I have hunted through with the search function and nothing similar has come up.
I logged into SL a short while ago only to find that I have 0 groups listed although all of my groups are showing in my profile.
I am also unable to access any of the pages in the groups that I belong to, including those that I am owner of.
I relogged and cleared cache manually, coming back with an empty cache folder, no change.
I used the Preferences option for SL to clear cache and relogged, still no groups.
Is this an SL problem that happens now and again? This is the first time I have encountered it.

I've had this recently, for the first time also. It seemed like a connection/network issue or perhaps something with the servers on SL's side. Regardless, it got better, don't worry. Kinda annoying though.

Thanks Leo. Annoying it sure is because it's preventing me building.
But I will give it some time and hopefully it will correct itself.

Bumping up in the hope that someone else might read this and offer a little advice.
Some 8 hours later, and being off-line for most of that time, I still have no groups showing in my groups tab although nothing has altered in my profile.
Does anyone have any idea why this would happen? Even better, any ideas how I can have them restored so that I can build in the areas where I am a member and issue notices in the groups that I own?

This happens sometimes when asset database servers are starting to fail from overload. good time to log out, go get a cup of coffee, relax, and come back later to log on again.