The actual Isolated Storage location is fixed but depends on the operating system where the Silverlight application is running:
From: http://msdn.microsoft.com/en-us/library/3ak841sy.aspx#isolated_storage_locations
| Operating system | Location in file system |
| Windows 98, Windows Me - user profiles not enabled | Roaming-enabled stores =
<SYSTEMROOT>\Application Data
Non Roaming stores = WINDOWS\Local Settings\Application Data |
| Windows 98, Windows Me - user profiles enabled | Roaming-enabled stores =
<SYSTEMROOT>\Profiles\<user>\Application Data
Non roaming stores = Windows\Local Settings\Application Data |
| Windows NT 4.0 | <SYSTEMROOT>\Profiles\<user>\Application Data |
| Windows NT 4.0 - Service Pack 4 | Roaming-enabled stores =
<SYSTEMROOT>\Profiles\<user>\Application Data
Non roaming stores =
<SYSTEMROOT>\Profiles\<user>\Local Settings\Application Data |
| Windows 2000, Windows XP, Windows Server 2003 - upgrade from Windows NT 4.0 | Roaming-enabled stores =
<SYSTEMROOT>\Profiles\<user>\Application Data
Non roaming stores =
<SYSTEMROOT>\Profiles\<user>\Local Settings\Application Data |
| Windows 2000 - clean installation (and upgrades from Windows 98 and Windows NT 3.51) | Roaming-enabled stores =
<SYSTEMDRIVE>\Documents and Settings\<user>\Application Data
Non roaming stores =
<SYSTEMDRIVE>\Documents and Settings\<user>\Local Settings\Application Data |
| Windows XP, Windows Server 2003 - clean installation (and upgrades from Windows 2000 and Windows 98) | Roaming-enabled stores =
<SYSTEMDRIVE>\Documents and Settings\<user>\Application Data
Non roaming stores =
<SYSTEMDRIVE>\Documents and Settings\<user>\Local Settings\Application Data |
| Windows Vista | Roaming-enabled stores =
<SYSTEMDRIVE>\Users\<user>\AppData\Roaming
Non roaming stores =
<SYSTEMDRIVE>\Users\<user>\AppData\Local |
The amount of data that you can put on the isolated storage is limited by the UserQuota property.
By default an application has 1MB of storage space.
(see http://msdn.microsoft.com/en-us/library/system.io.isolatedstorage.isolatedstoragefile.increasequotato(VS.95).aspx)
If more space is needed the user can call the method increaseQuotaTo() that will allow prompting the user for permision to increase the amount of storage.
This will show a prompt dialog like:
To define policies I recommed looked at the Group Policy settings page
http://www.microsoft.com/GetSilverlight/resources/documentation/grouppolicysettings.aspx#isolated-storage and we might see more details about that in another post.