Disappearing Video Projects in a 30-PC Lab
Government Girls' Inter College has a 30-computer lab running Windows 10. Each PC has a 120 GB SSD with about 9 GB free, and all PCs are on the same LAN. Students in Class 12 save their 1.2 GB video projects to the Desktop of whichever PC they use, then log in to a different PC the next day and report that their work has “disappeared”. A lab assistant runs a free-space script every Friday that deletes files in the Downloads folder older than seven days; last week the script was edited and also ran on the Desktop by mistake. Separately, a student's pen drive was pulled out during a file copy; the folder now shows files with 0 bytes, and a shared folder on the server has permissions set to “Everyone – Full control”. The principal wants a storage policy before the next practical exam.
1. Explain the most likely reason the projects appear to be missing, calculate whether storing 30 projects locally is feasible, and propose a storage plan for the lab.
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The Desktop is part of each local user profile, so a student who logs in on a different PC gets a different Desktop and cannot see the earlier file. The work has not necessarily been deleted; it is on the first PC's disk under that student's profile. Capacity makes local saving unworkable anyway: 30 × 1.2 GB = 36 GB, while each PC has only about 9 GB free. Even one class's projects exceed the free space on a single machine. The Friday script also created a real deletion risk by running on the Desktop. A sound plan is to create a network home folder per student on a server or NAS with at least 100 GB and nightly backup, map it as a drive, and train students to use Save As to that drive. Quotas, version history, and a corrected script that targets only Downloads and logs deletions would reduce recurrence. The Desktop should hold shortcuts, not the only copy.
2. The pen-drive folder shows files of 0 bytes after the drive was removed during copying. Explain what happened, why “Safely Remove Hardware” matters, and the immediate recovery steps.
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The operating system often acknowledges a write before all data has been flushed from cache to the pen drive. Pulling the drive out during a copy can cut power after the directory entry is created but before the data clusters are written, leaving a file name with size 0. It can also corrupt the FAT or directory structure. “Safely Remove Hardware” flushes pending writes, closes the file system, and dismounts the volume so removal is safe. For recovery, stop using the drive immediately and do not format or copy new files to it, because further writes may overwrite the lost clusters. Copy any surviving files to another drive first, then attempt recovery with a reputable tool; running chkdsk may repair the file system but can also make recovery harder, so it should be a deliberate choice. Prevention includes ejecting before removal, copying rather than moving, and keeping a second backup.
3. The shared folder grants “Everyone – Full control”. Explain the risk and design least-privilege permissions for students, teachers, and the lab assistant.
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“Everyone” includes guests and any local account, and Full control allows reading, changing, deleting, and altering permissions. Any student or infected machine could delete other students' work, plant malware, or encrypt the shared folder with ransomware. NTFS permissions and share permissions should be set so the most restrictive effective permission wins. Students should get Modify only on their own named folder and Read on common resources; they should not be able to browse or change other students' folders. Teachers should get Modify on class folders and Read on the common area. The lab assistant should get Full control only on a separate backup/administration folder, not on all student work. Remove the Everyone entry, use authenticated group accounts, enable access-based enumeration and auditing, and keep offline backups. This is least privilege: each person gets only what the task requires.