Nigel Robinson from Hull has been banned from being alone with his daughter, after accidentally downloading indecent images of children.
The 43-year-old called police after photos of young girls appeared on his computer when he was downloading music from a file-sharing website.
The scaffolder called Humberside Police to report the images in the hope that those responsible for uploading the pictures would be caught.
Officers launched an investigation, resulting in the laptop being confiscated and Mr Robinson being told he could not have unsupervised access to his eight-year-old daughter.
Mr Robinson, 43, said he has since been told it could take a year until his laptop is examined.
He told the Hull Daily Mail: "It has been a nightmare. I feel like I am guilty until proven innocent."
He added: "Whoever was uploading this will be miles away by now, yet I'm under the finger of suspicion."
Mr Robinson told the newspaper he was trying to download a new album by Slash from a website but, when he opened the folder, the files all had girls' names.
He said he opened some of the files and realised they were images of young girls.
He contacted the police at his wife's suggestion and officers confiscated his laptop for examination.
Mr Robinson was then told by East Riding of Yorkshire Council's social services department that he was not allowed unsupervised contact with his daughter.
The restriction, believed to be a voluntary arrangement, was made in November last year and will stay in place until the conclusion of the investigation.
A spokesman for East Riding of Yorkshire Council said: "The council's social care team considers that, on the information it presently has about this case, it is a proportionate response to request that Mr Robinson should not have unsupervised access with his own or other children.
"The council will keep the case under review but cannot comment further as this is an on-going investigation."
A Humberside Police spokeswoman added: "Humberside Police are currently conducting an investigation, which has resulted in the confiscation of a laptop computer, in order for the relevant inquiries to take place. This is a standard procedure for this type of investigation.
"The laptop is sent away to be examined and, as this forms the basis for a number of different investigations, Humberside Police have no control over the amount of time it takes for the laptop to be returned."