Desktop does not appear

I have just updated to version 19.1.1.3.

 

However, the Desktop very briefly appears, then disappears, and a "Documents" page turns up.   I can click the Documents page off for the Desktop to reappear.   Is there some way that I can get the Desktop to stay when I start up?   This has only occurred since updating to version 19.1.1.3.

 

I hope I have made this clear.   I would be pleased to receive your advice.

 

Adelaide