using System;
using System.Text.RegularExpressions;
 
public class Test
{
	public static void Main()
	{
		var s = "w:/a\\bc::/12\\xyz";
		var r = new Regex(@"^\p{L}+[\p{L}\d:]*/[\p{L}\d]+\\[\p{L}\d]+$", RegexOptions.Compiled);
		//The pattern is alphabets then zero or more numbers,alphabets,colon//
		//then forward slash then one or more numbers,alphabets then backward slash//
		//then again one or more numbers,alphabets
		for (var q = 0; q < s.Length; ++q)
			for (var w = q; w <= s.Length; ++w)
			{
				var cur = s.Substring(q, w-q);
				if (r.IsMatch(cur))
					Console.WriteLine("FOUND: {0}", cur);
			}
	}
}

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