A 6.2 GB Video, a 32 GB Pen Drive and a 4 GB Wall
An operator must hand over a 6.2 GB video recording of a district function. The only pen drive available is a 32 GB stick, currently holding 900 MB of scanned PDFs, formatted FAT32. Copying the video fails with the message The file is too large for the destination file system. Windows reports the drive as having 29.8 GB capacity. A 500 GB portable hard disk is also available, and the office PC's own C: drive is a 500 GB disk that Windows shows as 465 GB. The receiving computer is an office PC running Windows 7, and the same video must also be played from the pen drive on a classroom LED TV with a USB port. The operator considers zipping the file or burning DVDs (4.7 GB single-layer).
1. Explain precisely why the copy fails on a 32 GB drive, and evaluate each of the three workarounds: zipping, splitting, reformatting.
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The limit is per file, not per drive. FAT32 cannot store a single file larger than 4 GiB minus one byte, because its directory entry stores the file size in a 32-bit field. A 6.2 GB video exceeds that as one file, no matter how much free space the 32 GB stick has.
- Plain zipping will not work. The video is already compressed; the archive stays above 4 GB and still cannot be written. A split archive (7-Zip volumes of, say, 3.9 GB) does work, because each volume is a separate file under 4 GB - but the recipient must rejoin the parts before playing, which is fragile in an office.
- Reformatting to exFAT or NTFS removes the 4 GB limit entirely and is the cleanest fix, at the cost of erasing the drive - so the 900 MB of PDFs must be copied off first and restored afterwards.
- DVDs technically work (6.2 GB needs two 4.7 GB discs, roughly 4.38 GiB usable each) but produce two halves that must be played separately.
The drive is not faulty and has not lost capacity; the file system, not the hardware, is the constraint.
2. Reconcile the numbers: a 32 GB stick showing 29.8 GB, and a 500 GB disk showing 465 GB. Has capacity been lost?
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Nothing has been lost. The two figures use different units with the same name.
Drive manufacturers state capacity in decimal SI units: 1 GB = 1,000,000,000 bytes. Windows divides by binary units: 1 GiB = 1,073,741,824 bytes, but labels the result 'GB'.
- 500 GB disk: 500 × 10⁹ ÷ 2³⁰ = 465.7, shown as 465 GB.
- 32 GB stick: 32 × 10⁹ ÷ 2³⁰ = 29.8, shown as 29.8 GB.
The arithmetic matches the observed figures almost exactly, which is the check that the drive is genuine. The small residual difference on the pen drive comes from the file system's own structures - FAT, root directory, and on some sticks a small hidden utility partition.
This matters practically. A user who believes a 32 GB stick has shrunk may buy a replacement unnecessarily; a user who believes a 500 GB disk has lost 35 GB may suspect a fault or a virus. Understanding the conversion also lets you spot a counterfeit drive, where the discrepancy is far larger than the arithmetic predicts.
3. Given that the stick must work on a Windows 7 office PC, an Android phone and a classroom LED TV, which file system would you choose and what would you check before formatting?
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Choose exFAT.
- It has no 4 GB per-file limit, so the 6.2 GB video fits as one file.
- Windows 7 supports it natively (Service Pack 1 and later), including formatting it.
- Android supports exFAT on most current devices, with read support widespread even where write support varies.
- Most LED TVs manufactured from roughly 2012 onwards read exFAT, and virtually all read FAT32.
Why not the alternatives: FAT32 is disqualified by the 4 GB limit. NTFS is fine on Windows 7 and on many Android devices, but a large number of televisions read NTFS only in one direction or not at all - the one target we cannot test in advance is the weakest link.
Before formatting, in order: copy the 900 MB of PDFs to the PC and verify the copy opens; confirm the TV's supported formats from its manual or by testing a small exFAT stick first; then format, copy the video, and test playback on the TV before the drive leaves the office. Reformatting is destructive, and the TV is the only device whose behaviour cannot be predicted from the specification sheet.