The RadSpreadsheet component Protection feature uses hashing algorithms. When the FipsAlgorithmPolicy is enabled in Windows using the Protection feature causes an InvalidOperationException.

Applying a Number number format in a cell and then entering fractional number values like 1.2/2 results in cell value equal to 37258 if it is formatted as a date it will be 1/2/2002.

The exception is thrown when pasting in a protected sheet and canceling the warning message box using the MessageShowing event.

When entering values in the cells fast some of the values are skipped.

The SheetSelectorTabItem background is not properly applied and the text is not readable. This is easily noticeable in themes with a dark color palette. 

Currently, when the user is editing a cell and saves the document without leaving the edit mode first, the current value is not preserved in the saved document.
When pressing the File -> Save button in the ribbon, the Save dialog doesn't appear at all.
Workaround: Manually commit the change before saving. This workaround will also respect data validation:

When a user setups a page and chooses to customize the Header's Odd and Even pages, the tab headers become clipped.

When Esc key is pressed charts dialog should close.

Customers are reporting an issue when trying to copy content in an application hosted on a remote machine (there are reports using TigerVNC and Citrix).  The exception is thrown from the Clipboard class with a message: OpenClipboard failed (Exception from HRESULT: 0x800401D0 (CLIPBRD_E_CANT_OPEN))

It seems like such a behavior could be reproduced when the clipboard is already opened by another application. Here is a discussion on the matter: https://stackoverflow.com/questions/68666/clipbrd-e-cant-open-error-when-setting-the-clipboard-from-net

Resizing images always position the image at the cell where the image has been inserted. Flipping image also results in a wrong behavior.

Add support for formats which can present numbers with non-arabic numerals, for example:
- Bengali - [$-bn-IN,500]0
- Devanagari - [$-hi-IN,400]0
- East Arabic - [$-ar-SA,200]0
- Persian - [$-ar-SA,300]0
- Gujarati - [$-gu-IN,700]0
- Kannada - [$-kn-IN,B00]0
- Khmer - [$-et-EE,1200]0
- Lao - [$-lo-LA,E00]0
- Malayalam - [$-ml-IN,C00]0
- Mongolian - [$-mn-MN,1300]0
- Burmese - [$-my-MM,1000]0
- Oriya - [$-or-IN,800]0
- Tamil - [$-ta-IN,900]0
- Telugu - [$-te-IN,A00]0
- Thai - [$-th-TH,D00]0
- Tibetan - [$-bo-CN,F00]0

The item is closed as a duplicate. Please, vote and follow the item at https://feedback.telerik.com/wpf/1354143-spreadsheet-add-support-for-number-formats-for-presenting-numbers-with-non-arabic-numerals.

When you chose the Expand XAML option of the RadSpreadsheetRibbon control, the Charts group which should be in the Insert tab, is missing.

Add support for visualizing and editing charts.

Some of the RadSpreadsheet child controls do not apply the new theme, but stay with office black applied when theme is set on control level.

ArgumentException is thrown when protecting a worksheet having missing algorithmName information

Xlsx documents with a global filter defined cannot be imported. Message box "The name that you entered is not valid." is shown and internally SpreadsheetNameException is thrown. MS Excel can import such document and even preserve the filter, but do not respect it and doesn't have UI to clear it.

Workaround 1 (includes processing the document with MS Excel):
- Open the document in MS Excel
- Choose Formulas -> Defined names -> Named Manager
- Choose Filter -> Names with errors
- Find all Filter defined names and delete them
- Save the document

RadSpreadsheet should respect negative time values as MS Excel does it.

At the moment when any of the properties are changed, e.g. the frozen panes, the UI is not notified and you have to export and import the file in order for the UI to pick them up. 


Workaround: There are several workarounds:

1. Change the active worksheet and return to the old one

2. Export and import the document

3. Change the workbook of the RadSpreadsheet to a new one, and return the old one after that
4. Freeze the active worksheet using the ActiveWorksheetEditor.FreezePanes() method and freeze all others using the ViewState:
RadWorksheetEditor editor = this.radSpreadsheet.ActiveWorksheetEditor;
editor.FreezePanes(new CellIndex(3,3));
foreach (var worksheet in this.radSpreadsheet.Workbook.Worksheets)
{
    worksheet.ViewState.FreezePanes(5, 5);
}

We should provide an easier API allowing the customers to remove the key bindings or change the commands that they trigger.

Workaround: There is attached a sample showing how all the commands triggered by the key bindings can be disabled.

The AM/PM value is not shown in the cell when formatting a time value.

Steps to reproduce:
1. Insert some time in a cell in spreadsheet (22:20)
2. Apply it a custom format that contains AM/PM (e.g. "h:mm AM/PM")

Observed: The AM/PM format is missing
Expected: AM or PM should be shown after the time (image attached) 

Declined: The changes could be applied if the user presses OK button instead of pressing Enter key. A new feedback item is open where the issue is described: https://feedback.telerik.com/Project/143/Feedback/Details/212042-spreadsheet-custom-number-type-values-in-format-cells-dialog-are-not-applied-wh