Sun Room Leak

[alarmnovice25]

In the last few years we have had a stone sun room built onto the side of the house, however, it appears to be taking water in and I can't work out where from!

The pointing is in good condition, the guttering is free of debris and the lead flashing also looks to be in good condition although I think this may be the weak point and the use of cement instead of sealant could be an issue. I've also noticed recently that in the corner where the wall meets the ceiling, the damp spot has been getting worse which seems to suggest that is the point where it is taking water in. The house does take a battering on this side from wind and rain, can anybody suggest what to try next?

Thanks

 

[RandomGrinch]

Sorry, I'm not an expert, but I would suggest having a good look around the gutter area, up a step ladder, in some heavy rain (sorry!).
Is the gutter free flowing, or is water pooling at that end. I think I can see a stop end on the gutter, but is it leaky?