The version of the controls you have is extremely old and is part of the RadControls for ASP.NET "Classic" era. This suite has been deprecated and has not been supported for over 5 years, i.e., before the advent of VS2010 or any of the modern browsers (It does not support IE8 or above, Chrome, Firefox). Thus, we cannot guarantee it will work with VS2010 (although there shouldn't be issues, it is supposed to be backwards compatible) or with any of the current browsers in use.
You do not have to switch to the current UI for ASP.NET AJAX suite, but I would advise that you do so, because you will get:
- support for the current browsers and VS versions
- probably about 50 more controls than your current version
- a myriad of other features
Such an upgrade will be a heavy task, because there have been a lot of changes, however. There are help articles in the old controls' documentation that can help you with migration, like this one or this one (and other controls have them in a similar place). The online demos and documentation can also help you with implementing the features with the current version of the controls.
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