Everything about ViceVersa Snapshots

[TGRMN Software]

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Summary - what a ViceVersa snapshot is
- A snapshot is a frozen image (file) containing information about the contents of a folder (files and subfolders).
- It is used only for comparison/verification - you cannot copy to, delete from or synchronize a snapshot.
- Typical use: record a folder state and later compare the live folder against the snapshot to detect added/changed/deleted files or verify integrity.

Snapshot file types
- ViceVersa Snapshot (*.vsn) - proprietary binary. Recommended default. Can include CRCs.
- ViceVersa Snapshot with SHA values (*.sha) - binary and includes SHA-256 values for files (strong content verification).
- Simple File Verification (*.sfv) - text format containing CRCs. Widely supported but does NOT store file Timestamp and Size (so SFV cannot be used for timestamp/size comparisons). Note: ViceVersa does support saving/reading subfolder info into SFV while many apps don't.
- Comma Delimited (*.csv) - text file, one file per line, comma separated fields.
- Tab Delimited (*.txt) - text file, one file per line, tab separated fields.

What a snapshot can contain / verification options
- File list (names and subfolder structure).
- Timestamp and Size (unless saved to SFV which lacks timestamp/size).
- Optional CRC values (you choose when saving). If you omit CRCs the snapshot cannot be used for CRC comparisons (faster to create without CRCs).
- SHA snapshots include SHA-256 hashes for stronger verification.

How to create snapshots
1) From ViceVersa Comparison Window:
- Run a compare, then use Lists → Save → "Save Source to a File...", "Save Target to a File..." or "Save Selected to a File...".
- Choose file name, location and snapshot type; choose whether to include CRC (for non-SFV types).
- Quick trick: you can create a snapshot without running a full compare by setting Source or Target to "<blank>" before pressing Compare - this opens the Comparison Window and lets you save the folder as a snapshot.

2) From Windows File Explorer (Folder Snapshot Extension):
- Install the Folder Snapshot Extension (separate installer). After install, right‑clicking a folder shows:
- Create Snapshot - creates snapshot.vsn in that folder (includes timestamps & subfolders).
- Compare vs Snapshot - launches ViceVersa and compares the folder vs snapshot.vsn in that folder.
- On Windows 7/8/10/11/Server (and newer): hold Shift + right‑click to access extra commands:
- Create CRC Snapshot / Compare vs CRC Snapshot - same but includes/comparisons use CRC values.
- Create Snapshot (Run as Administrator) and Create CRC Snapshot (Run as Administrator) - run elevated when required (useful for protected folders).
- To disable those Explorer commands, uninstall the Folder Snapshot Extension.

How to use snapshots for comparison
- In ViceVersa, put the snapshot file path in the Source (or Target) and the live folder in the other side, then Compare. ViceVersa will show differences (deleted/changed/added).
- You can also right‑click a snapshot file in Explorer and choose "Compare ViceVersa Snapshot" (or "Compare ViceVersa Snapshot (with CRC)") to automatically compare the snapshot vs the folder where it sits.

Why snapshots are useful
- Integrity checks: verify that files on removable/media (CD/DVD) or archived folders have not changed (size/timestamp and especially CRC/SHA).
- Auditing: keep a record of a folder's state at a point in time and detect later changes.
- Quick offline comparison without needing a live source copy (snapshot is portable).
- Efficient verification when you need only to check that nothing changed, or to validate burned media contents.

Practical notes, limits and tips
- Recommended format: use the proprietary .vsn unless you need a text format or specific hash (use .sha for SHA-256).
- If you need CRC/SHA comparisons later, include CRC/SHA when saving. Saving without CRC is faster but limits verification. SFV always requires CRCs but lacks timestamps/sizes.
- Snapshots support subfolders.
- Snapshots are read-only: they can only be used to compare, not to sync/copy/restore.
- Default name when created from Explorer: snapshot.vsn (created in the selected folder).
- Use the Create (Run as Administrator) options if the folder needs elevated rights to list files.
- For quick creation without a full compare, set the other side to "<blank>" and open the Comparison Window, then save.

Related features (not the same as snapshots)
- Volume Shadow Copy (VSS) is a separate Windows feature ViceVersa can use to read open/locked files during a copy. VSS is for capturing live file contents during copy operations and is not the same as creating a snapshot file for later comparisons.
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TGRMN Software Support
http://www.tgrmn.com
http://www.compareandmerge.com