We have been using Lantastic since it came out and I had to link two computers together for the first time in our start up business. Lantastic has allowed me to slowly add faster and faster computers and relegate the older ones down the line with out interrupting the business or killing the cash flow. Older computers with older operating systems work flawlessly on the LAN. We have not found a software package that didn't run, but found that the software companies do not test for compatibility AND "don't support it" however it works just the same. We have missed the Virus problems by virtue of not using a "main stream" system. I am satisfied, greatful and pray for their continuing success.