To Enable Write-Protection - Sony CLIE PEG-S300 Operating Instructions Manual

Do not format Memory Stick media for Sony handheld with any application
other than MS Gate. Otherwise, the Memory Stick media might not work
correctly.
When you insert a Memory Stick media that was initialized by another
device, a dialog box appears asking if you want to format the Memory Stick
media. If you format it, you can use the Memory Stick media in your Sony
handheld. Note however, that all the data already stored on that Memory
Stick media will be deleted.
With some HACK software (e.g., DA software, etc.), your Sony handheld
might not recognize that a Memory Stick media is removed or inserted.
Close these applications when you use Memory Stick media.

To enable write-protection

Memory Stick media include a write-protect tab so that important data will
not be deleted by mistake.
Slide the tab to the right for write-protect mode, or to the left for unprotect
mode.
xNot write-protected
Slide the tab to the left for not write-protect mode. You can write data.
xWrite-protected
Slide the tab to the right for write-protect mode. You can read but not write
data. Use the write-protect mode when you do not want to write or delete
data on the inserted Memory Stick media.
Back side of the Memory Stick media.
LOCK
Not write-
Write-
protected
protected
LOCK LOCK
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