[Bing]

I had this form previous holder, it was planted next to raspberry, so I guess it is some sort of soft fruits, but could not identify the name. please help if you happen to know. thanks

[8doubles]

Looks like Herb Robert to me !

Just noticed the thorns, ignore the above !

[mumofstig]

Evergreen blackberries have leaves like that, so it's a blackberry hybrid of some sort.

[jaydig]

Many, many years ago I grew a 'thornless' blackberry that had leaves and stems (with thorns), that looked exactly like this. The plant didn't survive, but seedlings like the one in the picture have continued to be a problem anywhere and everywhere in the garden. It is almost impossible to get rid of it. 

[Bing]

holly! will dig out the roots & if it decide to grow out again, I  have the proper spray waiting!

[Salmo]

Cultivated blackberry or a seedling from one and will have beautifull big berries next year. Unless you have a lot of room to train it up a trelliss dig it out.

[Annen]

I've got that in my garden, it pops up from the back of the border and doesn't do anything except be prickly and difficult to get rid of. It doesn't look like a bramble (which also pops up from the back of the border)or any other fruiting plant.