I tried creating a EBCDIC to ASCII convector in C# using this general conversion order(given below). Basically the program converted from ASCII to the equivalent integer and from there into EDCDIC using the order below. Now when I try compiling this in C# and try giving a EBCDIC string(got this from another file from another computer) it is showing 'Out of Bound' exception for some of the EBCDIC character. Why is this like this?? Is it about formating?? or C# ?? or windows? Extra: I tried just printing out all the ASCII and EBCDIC characters using a loop from 0..255 numbers but still its not showing many of the EBCDIC characters. Am I missing any standards? int[] eb2as = new int[256]{ 0, 1, 2, 3,156, 9,134,127,151,141,142, 11, 12, 13, 14, 15, 16, 17, 18, 19,157,133, 8,135, 24, 25,146,143, 28, 29, 30, 31, 128,129,130,131,132, 10, 23, 27,136,137,138,139,140, 5, 6, 7, 144,145, 22,147,148,149,150, 4,152,153,154,155, 20, 21,158, 26, 32,160,161,162,163,164,165,166,167,168, 91, 46, 60, 40, 43, 33, 38,169,170,171,172,173,174,175,176,177, 93, 36, 42, 41, 59, 94, 45, 47,178,179,180,181,182,183,184,185,124, 44, 37, 95, 62, 63, 186,187,188,189,190,191,192,193,194, 96, 58, 35, 64, 39, 61, 34, 195, 97, 98, 99,100,101,102,103,104,105,196,197,198,199,200,201, 202,106,107,108,109,110,111,112,113,114,203,204,205,206,207,208, 209,126,115,116,117,118,119,120,121,122,210,211,212,213,214,215, 216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231, 123, 65, 66, 67, 68, 69, 70, 71, 72, 73,232,233,234,235,236,237, 125, 74, 75, 76, 77, 78, 79, 80, 81, 82,238,239,240,241,242,243, 92,159, 83, 84, 85, 86, 87, 88, 89, 90,244,245,246,247,248,249, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,250,251,252,253,254,255 }; The whole code is as follows: public string convertFromEBCDICtoASCII(string inputEBCDICString, int initialPos, int endPos) { string inputSubString = inputEBCDICString.Substring(initialPos, endPos); int[] e2a = new int[256]{ 0, 1, 2, 3,156, 9,134,127,151,141,142, 11, 12, 13, 14, 15, 16, 17, 18, 19,157,133, 8,135, 24, 25,146,143, 28, 29, 30, 31, 128,129,130,131,132, 10, 23, 27,136,137,138,139,140, 5, 6, 7, 144,145, 22,147,148,149,150, 4,152,153,154,155, 20, 21,158, 26, 32,160,161,162,163,164,165,166,167,168, 91, 46, 60, 40, 43, 33, 38,169,170,171,172,173,174,175,176,177, 93, 36, 42, 41, 59, 94, 45, 47,178,179,180,181,182,183,184,185,124, 44, 37, 95, 62, 63, 186,187,188,189,190,191,192,193,194, 96, 58, 35, 64, 39, 61, 34, 195, 97, 98, 99,100,101,102,103,104,105,196,197,198,199,200,201, 202,106,107,108,109,110,111,112,113,114,203,204,205,206,207,208, 209,126,115,116,117,118,119,120,121,122,210,211,212,213,214,215, 216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231, 123, 65, 66, 67, 68, 69, 70, 71, 72, 73,232,233,234,235,236,237, 125, 74, 75, 76, 77, 78, 79, 80, 81, 82,238,239,240,241,242,243, 92,159, 83, 84, 85, 86, 87, 88, 89, 90,244,245,246,247,248,249, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,250,251,252,253,254,255 }; char chrItem = Convert.ToChar("0"); StringBuilder sb = new StringBuilder(); for (int i = 0; i < inputSubString.Length; i++) { try { chrItem = Convert.ToChar(inputSubString.Substring(i, 1)); sb.Append(Convert.ToChar(e2a[(int)chrItem])); sb.Append((int)chrItem); sb.Append((int)00); } catch (Exception ex) { Console.WriteLine("//" + ex.Message); return string.Empty; } } string result = sb.ToString(); sb = null; return result; }