Microsoft has received a mixed response from resellers after it signalled a toughened stance on licence compliance in a controversial letter sent to its partners.

The software giant has been criticised as lacking subtlety by resellers which are angry that the letter implied a possible involvement in selling unlicensed software.

The opening paragraphs of the letter read: "Recently you have been buying fewer copies of Microsoft Office Professional from authorised Microsoft original equipment manufacturer distributors.

"We understand that competition for business is intense and that it is getting even tougher.

"Some system builders try to undercut their competitors by selling and installing copies of [software], making the situation worse for those selling licensed Microsoft software."

Mike Lawrence, managing director at reseller Bentpenny, said that the correspondence had left him fuming.

"We have never sold any illegal software and [the letter] implies that a reduction in orders is the result of illegal copies being sold when it is actually because the market is at saturation," he explained.

Caroline Smith, marketing programmes manager of the UK Compliance Group at Microsoft, claimed that there was never any intention of accusing anyone of wrongdoing.

She described it as an important "buyer beware" message aimed at raising awareness of the problem of high quality counterfeit products being sold in the channel.

Gordon Davies, commercial director at reseller Compusys, backed Microsoft's letter, suggesting that its "softly, softly approaches have failed".

"Perhaps it could have been more subtle, but we don't mind getting our toes trodden on a little if it solves the problem of serious criminal activity," he said.

"I support Microsoft because resellers that buy legitimately are suffering. We know the costs of these products and, if you break down some of the PC deals available, which are too cheap, you have to ask questions."

Smith added: "Microsoft is committed to protecting its legitimate channel and customers from unscrupulous traders so that they get what they think they paid for.

"Many partners have been duped into unknowingly buying and selling counterfeit products and therefore putting their business at risk."