Water Line Clog

Borax is alkaline. Try putting a few ounces of straight vinegar into the bottle, as it is quite acidic. It might foam a bit, but it should eventually "burn through" the Borax clog if you leave it a day or two.

(Picture that!)

When the ice maker calls for water, the valve sends water to the ice maker in the appropriate amount and then shuts off, sending no more water until the ice maker calls for it again. If the water fill line is freezing up, this will cause a leak the next time the ice maker calls for water. The water has to go somewhere. The problem is more than likely the the water valve. It is not shutting off completely and it is allowing a small trickle of water to be constantly sent to the ice maker. This causes the fill line to freeze up and clog. Replace the water valve and defrost the water fill line and solve the problem.

Could be a clog. Open the brew head a insert something small (like a paper clip) into the water output shaft. Swirl it around to break up any deposits there and then run again (without a k-cup). If water comes out but not correctly, repeat cleaning. Also, check to see if hot water is being deposited back into the tank. This will indicate a clog in the output line (line or, more likely, the head). If cleaning the head does not work, then reset the machine by unplugging and plugging back in.

check water line is open, check filter seated properly,make sure of on/off lever or switch or turn off water supply to fridge and check line for possible clog, and also on filter

First, I'm not JURA technician. But I have worked on similar table top "Super Automatics" You should call your vendor or the MFR for service. Especially if it's still under warranty. There are no customer serviceable parts in this machine.
*** the following is for information only ***
- Water not getting to machine or not sensing that the water tank is already filled.
* There usually some type of float near to middle of the water tank. It's usually white or colored plastic. This 'float' needs to move freely up-down to 'sense' the filled tank. clean the tank and shake it -note the movement of this float. It will need further cleaning if it's stuck (or you will have to replace tank if it's crudded up).
* Re-install tank and fill with filtered water. Turn machine off, count to 15 then turn on again. This usually turns on pump to add water to inner tank. If this does not happen then there is a CPU problem. If it does hums for 5-10 seconds then goes off but no heating then the pump may have an air bubble in line. Try the turn off and on method several times (up to 5) to get the water flowing. If it's still not working then there is a clog in the pump and will need service and/or replacement.
* Since this is a table top machine in which you fill the water tank. Try to use filtered (bottled ok) water. Do Not use Distilled or 100% pure water as this type of water will eat out the metals from your machine! Some places use a water softener as it tends to be better for the machine long term (years).
* Still got problems? Check with vendor or MFR for service or replacement. Most machines of this type do not have serviceable parts or adjustments.
Aloha, ukeboy57

PS: I've noted this tank also uses a water filter (which is probably dry after sitting around for a year as you mentioned.) you will probably have to flush out the air in the filter prior to this unit's pump to work properly. I found a youtube vid that may help:
https://www.bing.com/videos/search?q=s7+Jura+capresso+expresso+not+filling&&view=detail&mid=FA80FAE0243927C50056FA80FAE0243927C50056&&FORM=VRDGAR

think you've already figured it out! clog could be in dw hose where it enters gd. check for kinks in hose. perhaps replace hose, if it looks funky! try running a sterilize cycle- the hot water may unclog the hose (if your machine has the option).
good luck!

Have you tablet cleaned it?

check your solenoid valve and security valve of boiler of the machine. make sure they are clean and work good, than you will have perfect espresso again.
if pump runs without your comand check up the swich of brewing coffee.

the water is coming from the freezer when is defrosts. the drain line is in the back wall of the freezer and may be clogged up with ice. clean out the freezer and pour some hot water in the very back of the freezer, this will hopefully unclog the drain. if not, then you have to take the back wall out of the freezer to get directly to the drain line. there should just be a couple screws holding it; it is just an aluminum or plastic panel.
 
if you already checked this and think it is a different problem then let me know, i will help you figure it out. 
Mike  

replace water valve and fill hoses