Check the registry entries:
Key Name: HKEY_CLASSES_ROOT\.iso
Value 0
Name: <NO NAME>
Type: REG_SZ
Data: Windows.IsoFile
Key Name: HKEY_CLASSES_ROOT\.iso\OpenWithProgids
Value 0
Name: AppXjqa1mpdt03v06zzw47a6jxc0w376s91x
Type: REG_NONE
Data:
Value 1
Name: Windows.IsoFile
Type: REG_SZ
Data:
Key Name: HKEY_CLASSES_ROOT\Windows.IsoFile
Value 0
Name: <NO NAME>
Type: REG_SZ
Data: Disc Image File
Value 1
Name: FriendlyTypeName
Type: REG_EXPAND_SZ
Data: @%SystemRoot%\System32\shell32.dll,-30602
Key Name: HKEY_CLASSES_ROOT\Windows.IsoFile\DefaultIcon
Value 0
Name: <NO NAME>
Type: REG_EXPAND_SZ
Data: %SystemRoot%\System32\imageres.dll,-5205
Key Name: HKEY_CLASSES_ROOT\Windows.IsoFile\shell
Value 0
Name: <NO NAME>
Type: REG_SZ
Data: mount
Key Name: HKEY_CLASSES_ROOT\Windows.IsoFile\shell\burn
Value 0
Name: MUIVerb
Type: REG_EXPAND_SZ
Data: @%SystemRoot%\System32\isoburn.exe,-351
Key Name: HKEY_CLASSES_ROOT\Windows.IsoFile\shell\burn\command
Value 0
Name: <NO NAME>
Type: REG_EXPAND_SZ
Data: %SystemRoot%\System32\isoburn.exe "%1"
Key Name: HKEY_CLASSES_ROOT\Windows.IsoFile\shell\mount
Value 0
Name: CommandStateSync
Type: REG_SZ
Data:
Value 1
Name: ExplorerCommandHandler
Type: REG_SZ
Data: {9ab3b1c9-3225-4bb4-93b6-bfb3c0d93743}
Value 2
Name: MultiSelectModel
Type: REG_SZ
Data: Document
Key Name: HKEY_CLASSES_ROOT\Windows.IsoFile\shell\mount\command
Value 0
Name: <NO NAME>
Type: REG_EXPAND_SZ
Data: %SystemRoot%\Explorer.exe
Value 1
Name: DelegateExecute
Type: REG_SZ
Data: {9ab3b1c9-3225-4bb4-93b6-bfb3c0d93743}
Key Name: HKEY_CLASSES_ROOT\Windows.IsoFile\tabsets
Value 0
Name: selection
Type: REG_DWORD
Data: 0x704
Keith