Northamber says its second-half sales and profits were hit by a "sales hiatus" caused by uncertainty surrounding Windows 10.
In its preliminary results statement for its full year ending 30 June 2015, the Chessington-based distributor also announced its long-standing chairman, David Phillips, wants to step back to a non-executive role at the age of 70.
Northamber recorded smaller losses and higher sales for its full-year 2015 - but its bright start to the year was not matched by its second-half performance.
The AIM-listed outfit blamed weaker second-half PC and peripheral sales on the "overly extended transition period driven by Windows 10".
For its fiscal 2015 ending 30 June, pre-tax losses fell 23 per cent to £886,000 on revenues that rose 4.1 per cent to £65.5m.
But the majority of the losses - £594,000 - came in the second half, which saw revenues hit £29.75m - down 17 per cent half on half and nine per cent year on year.
Northamber recently took the wraps off a new Solutions Division targeting the security, storage, server and networking sectors and Phillips said the need to abandon "empty revenue" has been heightened by the PC slowdown, as documented by the likes of IDC and Gartner.
"The current sales hiatus for both hardware and peripherals, driven by insufficient certainty within the commercial user sector, is beyond any influence we might have and is totally driven by understandable caution and uncertainty surrounding Windows 10," Phillips said. "That has driven an even greater spur to the pace of implementation of our planned strategy."
"After too many years in this sector, we remain prudently optimistic that we will continue to reverse the trend in the company of the last few years and provide a profitable business for the future."
Having founded Northamber in 1979, Phillips said the fact he is now in his 70s means it is "clearly time" to downsize his executive role.
"The search for an executive managing director is already under way," he said.
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