A branch of disability charity Scope, in Station Road, was broken into after opening hours overnight between Wednesday (August 16) and Thursday (August 17).
It is the second time the branch, which sells second hand clothes and books amongst other things at a discount price, has suffered at the hands of potential burglars.
According to Harrow Police , the break in took place between 7pm and 8am on Thursday August 17.
A spokesman for the borough force said: "The suspect has damaged the rear door but not managed to get inside, and therefore nothing was stolen thankfully.
"The same shop was broken into three weeks ago and had money stolen.
"We are examining the door for possible forensics and checking CCTV."
Scope, which has just launched its national Great Donate campaign , will keep its Harrow branch open despite the disruption.
Lara Woolston, retail area manager at Scope, said: "It is disheartening when anyone tries to break into a charity shop.
"A door had been damaged, but thankfully this time nothing was taken.
"Our staff and volunteers in Harrow work incredibly hard to raise vital funds for disabled people and their families.
"The shop remains open to serve the local community.
"We are right in the middle of our national donation drive and are appealing to everyone to make as many donations as possible to the shop."
To find out more about the Harrow branch and how to donate, click here .
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