I do not know who this is aimed at? but it comes across as quite offensive! Did you mean it to? If you need help putting a photo on here perhaps I can help you to do it?

I found my Red and White current bushes did not fruit in one part of my garden as the soil was so compacted that they were in affect root bound. It was also dry being next to a wall.

I moved them to a raised bed with some bone meal, full sun and well watered (esp this year!) and they have done well.

The RHS website has the best instructions for pruning Red current, so I quote:

1. From early June to mid-July, cut all young side shoots to five leaves and tie the growing tip to the cane as it extends.
2. In late autumn or winter, after leaf fall, prune back the same side shoots to one or two buds. Cut back the tip by one-third.
3. Once the cordon reaches 1.7m (5½ft) in height (the top of the supports), cut back the tip to five leaves from last year’s growth in the summer, and then back to one-three buds from last year’s growth in winter.

A combo of making sure the soil is not compacted so that the bush can spread its roots, has fertiliser and well watered and pruning as above should work.

Some folk don't know the difference. And it was only a loose comment, not intended to offend you. SORRY!
Ok so no picture. Prune out the some of the older branches to about 4" from the ground. Cut out any damaged or crossing branches. prune back some of the newer branches around the outside. Give a scratch around on the earth below and then give a heavy mulch with garden compost or manure or even both. Do all this in January or February.
And if you come over to my open day 19th August, you can have free entry and a quick demonstration on an old white currant bush.

If you are the Barbara I know from Keeston I will come over and have a look at it if you like
Sue