\r
if (stopwatch != null && stopwatch.IsRunning && stopwatch.ElapsedMilliseconds > 3000) {\r
long bpers = e.DownloadSize * 1000 / stopwatch.ElapsedMilliseconds;\r
- if (e.TaskProgressPercent >= 0) {\r
+ if ((e.TaskProgressPercent >= 0) && (bpers > 0)) {\r
TimeSpan rest = TimeSpan.FromSeconds((max - e.DownloadSize) / bpers);\r
e.TaskMessage += string.Format(" 推定残り時間:{0} ({1}/s)", rest, NaGet.Utils.FormatSize(bpers));\r
} else {\r