Conservative MP Greg Hands wrote to the commission in April, claiming a statement on the charity’s website made it clear that contact details of the charity’s supporters could be shared with "other organisations connected with Tony Blair". The charity was set up in 2009 to help African leaders tackle poverty.
Hands said he had signed up as a supporter of the charity, and had since received emails from a political campaigning organisation that asked him to support the Labour Party.
The Sunday Times reported that the commission had sent a letter to Hands saying that the charity had failed to take adequate steps to prevent its database from being exploited for political purposes.
A spokeswoman for the commission would not comment on the letter but confirmed that it had closed its assessment of the charity. She said it had issued "regulatory advice and guidance" to the initiative about charities and political campaigning, but would not take further action.
The commission’s guidelines on charities and political campaigning say charities "cannot give general support to a political party".
They say: "Where a charity, whether deliberately or by mistake, appears to be carrying out campaign activity that is not sufficiently connected to its purposes, we will look into this.
"We will generally aim to resolve such situations informally, but may need to take regulatory action where there has been misuse of charity resources or misconduct".
A spokesman for the charity said it had acted on the commission’s advice.
"It was obviously never the intention of the charity to send political information to any individuals interested in the Africa Governance Initiative’s activities," he said.
"The charity is completely non-political. Upon being alerted to this issue, the charity took immediate action, and has taken on board the advice offered by the Charity Commission."