Errors caused by data cleansing could leave corporate customers without the internet.
The error was first brought to our attention last week by a small firm of solicitors which found it was unable to get online. It contacted BT, which explained the service had been cut off because of an error on the databases. However, although it was the company's fault it offered no refund, apology or rush job, claiming that services wouldn't resume until the next day.
Data cleansing, also known as data cleaning, is a regular service carried out by large companies.
It is performed on any database of business or consumer records to keep data accurate and up-to-date. However, this time it went a bit wrong.
We contacted BT, which told us: "This was an oversight by BT after we performed a data cleanse of our databases.
"One database showed the account was live but another showed it was cancelled so we cut the service off.
"It was down to conflicting information and it was our fault, the service is scheduled to be switched on again tomorrow."
However when confronted about refunding, we were told it wasn't something that the department dealt with and we'd have to contact someone elsewhere.
This isn't the first time that this particular firm has had issues with the ISP. Late last year it was left high and dry for 10 days after BT failed to install services on a promised date. Again it held its hands up and apologised but again it didn't move to offer any compensation.
A member at the firm told TechEye: "We're only a small company and depend on broadband for our services. We were let down by BT before we had even had the service and now the service is cancelled through no fault of our own."
We contacted BT's press office to get some more information.
At the time of publication it was still looking into the matter - first asked this morning - and promised to get back to us as soon as it had further information as to what went wrong. It hasn't.