How Blober Handles Duplicate Files in Long-Running Backups

Long Backups Need Two Different Kinds of Protection
Section titled "Long Backups Need Two Different Kinds of Protection"A cloud library can take hours or days to copy. During that time, a computer may restart, a network may disconnect, or a provider may ask you to sign in again. You may also want to run the same export later to collect newer files.
Those situations sound similar, but they need different tools:
- Resume the existing task after an interruption. Blober keeps that task's progress and does not process its completed records again. This works on every provider and needs no setting.
- Use destination deduplication for a deliberate rerun. When a new task writes to the same destination, deduplication decides whether files that are already there are skipped or overwritten. This depends on the destination supporting it.
Understanding that distinction is the key to avoiding unnecessary transfers.
Workflow vs Task: What Blober Remembers
Section titled "Workflow vs Task: What Blober Remembers"A workflow is the reusable setup: source, destination, selected folders, filters, and naming rules. Each time you start that workflow, Blober creates a task that records the progress of that run.
Within a task, Blober records each source path as it is processed or skipped. If that task is interrupted and later continues, records already marked complete are not processed again.
This task state is stored locally with your workflows. Closing Blober, restarting the computer, or installing a newer version of Blober preserves the existing workflows and task history.
What to Do After an Interruption
Section titled "What to Do After an Interruption"- Reopen Blober.
- Find the existing task on the Progress page.
- If it was paused, resume that same task.
- If it was still pending or running when Blober closed, the app can rediscover it after launch and continue it automatically.
- Complete any provider login prompt that appears.
Do not start a new task merely because the original task stopped. A new run has its own progress records and is not a continuation of the interrupted run.
This matters especially for long cloud transfers. A provider login may expire during a run; signing in again refreshes access, while the existing task keeps its completed-file state.
What Blober Does When a File Already Exists
Section titled "What Blober Does When a File Already Exists"Deduplication is a destination setting that decides what happens when the exact destination path is already occupied:
- Skip if a file with the same name exists - the default. The file is not written, the record is marked skipped, and the run continues with the next file.
- Overwrite the existing file - the destination copy is replaced.
- Keep both files (rename the new copy) - available on Local destinations, which save the new file as
name (1).ext, thenname (2).ext.
The comparison is the destination path: destination folder, path template, and filename. File contents are never compared.
Not Every Destination Supports Deduplication
Section titled "Not Every Destination Supports Deduplication"The control appears only for destinations that can act on an existing file:
- Source-only providers have nothing to deduplicate.
- GoPro Cloud cannot replace or compare by name, so a rerun writes the file again.
Azure Blob Storage adds one rule of its own: archived blobs are always skipped, whichever policy is selected, because an archived blob cannot be rewritten. Rehydrate the blob first if you want to replace it.
Skip Files That Are Already There
Section titled "Skip Files That Are Already There"For a repeat export where an exact existing destination path means "already transferred":
- Open or create the workflow.
- Select the destination.
- Open the destination configuration.
- Set Deduplication to Skip if a file with the same name exists.
- Save and run the workflow.
Blober checks the destination before it opens the source, and repeats the check when claiming the final filename, which also protects against two concurrent transfers racing to create the same path.
See Deduplication for the policies and the destinations that support them.
Which Option Should You Use?
Section titled "Which Option Should You Use?"| Situation | Recommended action |
|---|---|
| Blober, the computer, or the network stopped during a task | Resume the existing task |
| A provider asks you to sign in again during a task | Sign in, then continue the existing task |
| You installed a Blober update during a transfer | Reopen Blober and continue the existing task |
| You intentionally rerun an export into the same folder | Set Deduplication to Skip if a file with the same name exists |
| You want the destination copies replaced | Set Deduplication to Overwrite the existing file, where the destination supports it |
| The source may contain different files with identical names | Choose Keep both files (rename the new copy) on a Local destination |
| The destination does not offer deduplication | Resume the same interrupted task instead of rerunning; a fresh run transfers the files again |
Google Photos Reruns Without Numbered Copies
Section titled "Google Photos Reruns Without Numbered Copies"Google Photos is a common case because a large library may take a long time to download and may contain repeated camera filenames.
For an interrupted Google Photos download, continue the existing task. For a deliberate later export into the same local folder, use Skip if a file with the same name exists only when preserving one file per exact destination filename matches your library.
The full setup is covered in How to Back Up Google Photos Without Google Takeout. That guide and the Deduplication reference use the same setting described here.
Best Practices for Multi-Day Transfers
Section titled "Best Practices for Multi-Day Transfers"- Keep the computer connected to power and avoid moving or disconnecting the destination drive.
- Use a stable destination folder and path template for the whole task.
- Pause before intentionally shutting down if you want manual control over when the task continues.
- After an unexpected restart, reopen Blober before creating anything new and check the existing task first.
- Respond to provider login prompts instead of replacing the workflow.
- Review files marked failed or skipped after completion. A provider may temporarily make an individual file unavailable even though the rest of the transfer completed.
Frequently Asked Questions
Section titled "Frequently Asked Questions"Will updating Blober erase my workflows or task progress?
Section titled "Will updating Blober erase my workflows or task progress?"No. Installing an update preserves the local database that contains workflows, tasks, and per-record state. Reopen the existing task after the update rather than creating a replacement.
Does skipping by name compare file contents?
Section titled "Does skipping by name compare file contents?"No. It checks whether the exact destination filename already exists. It does not calculate or compare content hashes.
Does a skipped file count as complete in the same task?
Section titled "Does a skipped file count as complete in the same task?"Yes. Blober saves the reason in the task details and continues with the remaining files. This prevents one unavailable source file or an intentional destination duplicate from blocking the rest of the transfer.
Can I use deduplication with Google Drive?
Section titled "Can I use deduplication with Google Drive?"Yes, if the destination supports it. Google Drive destinations offer skip and overwrite. Check the destination configuration for the Deduplication control: if it is not shown, that destination cannot act on an existing file, and resuming the original task is the way to avoid transferring the same files twice.
Get Blober
Section titled "Get Blober"Blober runs on Windows, macOS, and Linux and is built for transfers that are too large to babysit in a browser.
