Datastore inaccessible

HI gurus

  I very new to VM ,so I hope I am posting in the right place.

I have a datastore that shows Inaccessible , all VM seems to be running ok as I take is because they are on different datastore repository, gurus, I need help resolving this datastore inaccessible problem, so I can learn, is the first time I face an error like this one.

Thanks

FB