Isolated Storage in Silverlight is a good place to persist any kind of user preferences. The problem: You cannot rely on Isolated Storage being available.
Even when “Enable application storage” is checked you may still get an
This can happen when private browsingis enabled (in all major browsers). Conclusion: Always check availability before accessing:
It can easily be turned of via the Silverlight context menu.

Even when “Enable application storage” is checked you may still get an

This can happen when private browsingis enabled (in all major browsers). Conclusion: Always check availability before accessing:
if (IsolatedStorageFile.IsEnabled)
{
// read/write isolated storage data
}
else
{
// do something else
}
Possible backup strategies:
1. Use cookies?
Well, not really. Cookies are deleted when a private browsing session ends.
2. Ask user?
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