you are prohibited from recording on thips tape. This is because the red tab on the side of the tape that faces you when you are inserting the tape inside the camera has been put in 'SAVE' position . to be able to record o the tape you need to use your fingernail to slide the red tab to the 'REC' position.
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Tape and recording protection
The write-protect switch (right) prevents accidental erasure.
To prevent the recording on the tape from being erased, there is a small write-protect tab that can be moved to one of two positions, labeled "REC" and "SAVE". Comparing the sliding tab to a door, the tape is in the "REC" position is when the "door" is open and the "SAVE" position when it is closed. (Not all tape cases have markings for this information!) The tape can only be recorded on (or recorded over) when this tab is in the "REC" position. This is an improved version of the VHS write-protect tab, which prevents erasure after it has been (permanently) broken off.