diff --git a/gxoffice/src/main/java/com/genexus/msoffice/excel/poi/xssf/ExcelCells.java b/gxoffice/src/main/java/com/genexus/msoffice/excel/poi/xssf/ExcelCells.java
index 6472df460..4faaf16e1 100644
--- a/gxoffice/src/main/java/com/genexus/msoffice/excel/poi/xssf/ExcelCells.java
+++ b/gxoffice/src/main/java/com/genexus/msoffice/excel/poi/xssf/ExcelCells.java
@@ -145,36 +145,39 @@ public BigDecimal getNumber() throws ExcelException {
 
     }
 
-    public boolean setDate(Date value) throws ExcelException {
-        CheckReadonlyDocument();
-        try {
-            if (!CommonUtil.nullDate().equals(value)) {
-				String dformat = ""; //this.doc.getDateFormat().toLowerCase();
+	public boolean setDate(Date value) throws ExcelException {
+		CheckReadonlyDocument();
+		try {
+			if (!CommonUtil.nullDate().equals(value)) {
+				String dformat = "m/d/yy h:mm";//this.doc.getDateFormat().toLowerCase();
 				Calendar calendar = GregorianCalendar.getInstance(); // creates a new calendar instance
 				calendar.setTime(value);
 				if (calendar.get(Calendar.MINUTE) == 0 && calendar.get(Calendar.HOUR) == 0
-						&& calendar.get(Calendar.SECOND) == 0 && dformat.indexOf(' ') > 0) {
+					&& calendar.get(Calendar.SECOND) == 0 && dformat.indexOf(' ') > 0) {
 					dformat = dformat.substring(0, dformat.indexOf(' '));
 				}
-
 				DataFormat df = pWorkbook.createDataFormat();
-				XSSFCellStyle newStyle = stylesCache.getCellStyle(df.getFormat(dformat));
 
 				for (int i = 1; i <= cellCount; i++) {
 					XSSFCellStyle cellStyle = pCells[i].getCellStyle();
-					copyPropertiesStyle(newStyle, cellStyle);
-					newStyle.setDataFormat(df.getFormat(dformat));
+					if (! DateUtil.isCellDateFormatted(pCells[i])) {
+						XSSFCellStyle newStyle = pWorkbook.createCellStyle();
+						copyPropertiesStyle(newStyle, cellStyle);
+						newStyle.setDataFormat(df.getFormat(dformat));
+						pCells[i].setCellStyle(newStyle);
+						fitColumnWidth(i, dformat.length() + 4);
+					}else {
+						fitColumnWidth(i, cellStyle.getDataFormatString().length() + 4);
+					}
 					pCells[i].setCellValue(value);
-					pCells[i].setCellStyle(newStyle);
-					fitColumnWidth(i, dformat.length() + 4);
 				}
-                return true;
-            }
-        } catch (Exception e) {
-            throw new ExcelException(7, "Invalid cell value");
-        }
-        return false;
-    }
+				return true;
+			}
+		} catch (Exception e) {
+			throw new ExcelException(7, "Invalid cell value");
+		}
+		return false;
+	}
 
     public Date getDate() throws ExcelException {
         Date returnValue = null;
diff --git a/gxoffice/src/main/java/com/genexus/msoffice/excel/poi/xssf/ExcelSpreadsheet.java b/gxoffice/src/main/java/com/genexus/msoffice/excel/poi/xssf/ExcelSpreadsheet.java
index 6cd6cb5ea..b6635a692 100644
--- a/gxoffice/src/main/java/com/genexus/msoffice/excel/poi/xssf/ExcelSpreadsheet.java
+++ b/gxoffice/src/main/java/com/genexus/msoffice/excel/poi/xssf/ExcelSpreadsheet.java
@@ -233,22 +233,24 @@ private void recalculateFormulas() {
         }
     }
 
-    private void autoFitColumns() {
-        if (_autoFitColumnsOnSave) {
-            int sheetsCount = _workbook.getNumberOfSheets();
-            for (int i = 0; i < sheetsCount; i++) {
-                org.apache.poi.ss.usermodel.Sheet sheet = _workbook.getSheetAt(i);
-
-                Row row = sheet.getRow(0);
-                if (row != null) {
-                    int columnCount = row.getPhysicalNumberOfCells();
-                    for (int j = 0; j < columnCount; j++) {
-                        sheet.autoSizeColumn(j);
-                    }
-                }
-            }
-        }
-    }
+	private void autoFitColumns() {
+		if (_autoFitColumnsOnSave) {
+			int sheetsCount = _workbook.getNumberOfSheets();
+			for (int i = 0; i < sheetsCount; i++) {
+				org.apache.poi.ss.usermodel.Sheet sheet = _workbook.getSheetAt(i);
+				int columnCount = 0;
+				for (int j =0; j <= sheet.getLastRowNum(); j++){
+					Row row = sheet.getRow(j);
+					if (row != null) {
+						columnCount = Math.max(columnCount, row.getLastCellNum());
+					}
+				}
+				for (int j = 0; j < columnCount; j++) {
+					sheet.autoSizeColumn(j);
+				}
+			}
+		}
+	}
 
 
     @Override
diff --git a/gxoffice/src/test/java/com/genexus/msoffice/excel/ExcelSpreadsheetTest.java b/gxoffice/src/test/java/com/genexus/msoffice/excel/ExcelSpreadsheetTest.java
index 8c4334dbe..220f49b2e 100644
--- a/gxoffice/src/test/java/com/genexus/msoffice/excel/ExcelSpreadsheetTest.java
+++ b/gxoffice/src/test/java/com/genexus/msoffice/excel/ExcelSpreadsheetTest.java
@@ -890,7 +890,7 @@ public void testHideRow2() {
 		excel.save();
 		excel.close();
 		// Verify previous Excel Document
-		excel = open("testHideRow");
+		excel = open("testHideRow2");
 
 		assertEquals(1, excel.getCell(1, 1).getNumericValue().intValue());
 		excel.save();
@@ -909,7 +909,7 @@ public void testHideRow3() {
 		excel.save();
 		excel.close();
 		// Verify previous Excel Document
-		excel = open("testHideRow");
+		excel = open("testHideRow3");
 
 		assertEquals(1, excel.getCell(1, 1).getNumericValue().intValue());
 		excel.save();
@@ -1018,6 +1018,67 @@ public void testSaveAs() {
 
     }
 
+	@Test
+	public void testAutoFit() {
+		ExcelSpreadsheetGXWrapper excel = create("testAutoFit");
+		excel.setAutofit(true);
+		excel.getCells(1, 2, 1, 1).setText("LONGTEXTTTTTTTTTTTTTTTTTTTTTTTTTTTTTT");
+		excel.getCells(1, 3, 1, 1).setText("VERYLONGTEXTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTT");
+		excel.getCells(2, 4, 1, 1).setText("hola!");
+		excel.getCells(6, 6, 1, 1).setText("VERYLONGTEXTINDIFFERENTROWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW");
+		ExcelCells cells = excel.getCells(7, 7, 1, 1);
+		ExcelStyle style = new ExcelStyle();
+		style.setDataFormat("#.##"); //change style, so it shows the full number not scientific notation
+		cells.setNumericValue(new BigDecimal("123456789123456789123456789"));
+		cells.setCellStyle(style);
+		excel.save();
+		excel.close();
+	}
+
+	@Test
+	public void testDateFormat() {
+		ExcelSpreadsheetGXWrapper excel = create("testDateFormat");
+		excel.setAutofit(true);
+		Date date = new Date();
+		//sets date with default format
+		ExcelCells cells = excel.getCells(1, 1, 1, 1);
+		cells.setDateValue(date);
+		//sets date and apply format after
+		cells = excel.getCells(2, 1, 1, 1);
+		ExcelStyle style = new ExcelStyle();
+		cells.setDateValue(date);
+		style.setDataFormat("YYYY/MM/DD hh:mm:ss");
+		cells.setCellStyle(style);
+		//sets date and apply format before
+		cells = excel.getCells(3, 1, 1, 1);
+		style = new ExcelStyle();
+		style.setDataFormat("YYYY/MM/DD hh:mm:ss");
+		cells.setCellStyle(style);
+		cells.setDateValue(date);
+
+		date.setHours(0);
+		date.setMinutes(0);
+		date.setSeconds(0);
+		//sets date with default format without hours
+		cells = excel.getCells(4, 1, 1, 1);
+		cells.setDateValue(date);
+		//sets date and apply format after
+		cells = excel.getCells(5, 1, 1, 1);
+		style = new ExcelStyle();
+		cells.setDateValue(date);
+		style.setDataFormat("YYYY/MM/DD hh:mm:ss");
+		cells.setCellStyle(style);
+		//sets date and apply format before
+		cells = excel.getCells(6, 1, 1, 1);
+		style = new ExcelStyle();
+		style.setDataFormat("YYYY/MM/DD hh:mm:ss");
+		cells.setCellStyle(style);
+		cells.setDateValue(date);
+
+		excel.save();
+		excel.close();
+	}
+
     private void logErrorCodes(ExcelSpreadsheetGXWrapper excel) {
        // System.out.println(String.format("%s - %s", excel.getErrCode(), excel.getErrDescription()));
     }