Duncan Reid, UK licensing manager at Microsoft, said the company had approached the OFT and DTI after press coverage - including Computer Weekly's hard hitting campaign - expressed widespread user anger.
Some companies have estimated that software costs will more than double and corporate IT user group The Infrastructure Forum (Tif) recently called on the OFT to investigate whether Microsoft has breached monopoly rules in the Competition Act.
The OFT has wide ranging powers - it could order Microsoft to abandon the changes in the UK or tell the company to suspend them while it investigates. Under the Act, firms that break the rules can be fined up to 10% of their UK turnover.
Reid said Microsoft was keen to get its side of the story across. "We wanted to make sure the OFT and DTI had a clear view of what the licensing changes actually mean," he said.
An OFT spokesman said it would welcome more.