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The U.S. case on tying the MicroSoft (MS) Internet Explorer to Windows has received much attention. In Europe, a similar case of tying the MS media player to Windows appeared. Recently in Korea, another similar case of tying the MS messenger to Windows occurred. In the messenger-tying case (as well as in the other tying cases), the main defence of MS seemed to be three-fold: (i) tying enhances efficiency, (ii) the MS product is better or better marketed, and (iii) tying is inconsequential because the user can easily download free competing products. This paper empirically addresses the third point. Korean data, used as an evidence in the trial of the case, reveal that tying the MS messenger (MSM) to Windows increased the probability of choosing MSM as the main messenger by about 22-35%. There is also an evidence that the tying shortened the duration until MSM adoption by about 2-4 months, compared with the duration until the adoption of a competing messenger. Hence tying provided MS an almost instant advantage in the messenger market "race"---the advantage derived from the dominant position in the operating system market. This advantage "at the start line" became further magnified by large lock-in and network effects, which are also empirically documented in this paper.