The main reasons given by directors were that they did not have a clear understanding of what the business required from IT. They also experienced unexpected problems when integrating systems.
Of the 3,080 companies surveyed by financial software supplier Sage, 41% said they had received poor customer service from their supplier.
Some 44% of SMEs with more than 100 employees said they had wasted money on IT, with 46% citing loss of staff hours because of problems with technology.
Paul Stobart, UK managing director of Sage, said, "Some of the findings are surprising. Historically the [IT industry] has not done enough [to ensure products can work together]. There is a sense we should stop trying to sell tomorrow's dream and sell more pragmatically."
He said SMEs should be clear about what they want from IT when dealing with suppliers.
Peter Scargill, national IT chairman of the Federation of Small Businesses, said the research showed the need for SMEs to invest more in IT staff training.
"You can split the blame between suppliers and companies, but companies expect too much from too little investment in the IT skills of their staff," he said.
IT is the third most pressing issue after financial and legal issues for seeking external advice, but businesses are unlikely to turn to a supplier for help, the research found. A third of respondents said friends, family and colleagues were the main sources of advice.