Event ID 163: MftBitmap is not big enough for MftData or does not have required allocations
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Windows 10.0.26200.0, 2026-10-28; the notes are ours, based on Microsoft's
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MftBitmap is not big enough for MftData or does not have required allocations.
Event 163
Ntfs
System log
Warning
Message and fields (as Event Viewer shows them)
MftBitmap is not big enough for MftData or does not have required allocations.
Volume correlation Id: …
Volume name: …
Volume label: …
Device name: …
Device GUID: …
Device manufacturer: …
Device model: …
Device revision: …
Device serial number: …
Bus type: …
Native NVMe: …
Adapter serial number: …
Mft data allocation size: …
Mft data file size: …
Mft bitmap allocation size: …
Mft bitmap file size: …
Bytes per FRS: …
Mft data attribute allocation size: …
Mft data attribute file size: …
Mft bitmap attribute highest Vcn: …
Mft bitmap attribute allocation size: …
Mft bitmap attribute file size: …
Last data and bitmap attribute record in Mft are in same FRS: …
Called from worker: …
Livedump worker status: …
Major function: …
Minor function: …
Source tag: …