How to Handle SharePoint Throttling in ReplaceMagic

Understanding and Avoiding SharePoint Throttling

Download ReplaceMagic Videos: How to use ReplaceMagic

SharePoint Online (and sometimes on-premises) rate-limits API calls to protect platform stability. When too many requests arrive too quickly, SharePoint returns HTTP 429 (Too Many Requests) or 503 errors — this is called throttling. ReplaceMagic has built-in tools to handle throttling automatically.

ReplaceMagic can process multiple number of documents in parallel but you'll need to avoid getting throttled or blocked in SharePoint Online. Of course, this is great for performances but SharePoint platform (based on internal rules) might decide that workload created by ReplaceMagic is too high. As a consequence SharePoint might slowdown processing or even block it.

This is mainly on SharePoint.Online side but also might apply for your SharePoint on-premise depending what your SharePoint administrators configured.

To control workload (parallelization) created by ReplaceMagic you can use parameter "Parallel document processing" which is in Configuration tab (click on Configuration button in main ReplaceMagic form):



Depending on SharePoint configuration this number can be higher or lower but we recommend that you start with 3-5 and then do fine tuning depending how your SharePoint platform behaves.

More about SharePoint throttling can be found here

What Causes SharePoint Throttling

• Too many parallel document processing threads hitting the SharePoint API simultaneously
• Processing during peak hours when other users and services are also making API calls
• Very large document libraries processed without any rate limiting
• Tenant-wide throttling: if your entire Microsoft 365 tenant is under heavy load, any application can be throttled

How ReplaceMagic Handles Throttling Automatically

• Enable "Decrease workload during SharePoint Throttling" in Configuration → Configuration tab
• When a 429/503 error is detected, ReplaceMagic automatically reduces parallel processing
• Enable "Optimize workload every X documents" to let ReplaceMagic gradually increase parallelism again once throttling subsides
• The "SharePoint workload safety belt" option caps parallel processing at a maximum of 8 documents for any SharePoint target

Recommended Settings for SharePoint Online

• Start with 3–5 parallel threads (Configuration → Configuration tab → "Parallel document processing")
• Enable both "Decrease workload during SharePoint Throttling" AND "Optimize workload" for automatic management
• For very large libraries or tenant-wide migrations, consider running during off-peak hours (nights and weekends)
• If throttling persists even at low parallelism, contact your Microsoft 365 admin — tenant-level resource limits may be in play

SharePoint On-Premises and Throttling

• SharePoint on-premises can also throttle, especially older 2013/2016 versions
• On-premises throttling is typically less aggressive than SharePoint Online
• The same configuration settings apply: reduce parallel processing if on-premises throttling errors occur
• Check your SharePoint administrator's resource throttling policies

Download ReplaceMagic Videos: How to use ReplaceMagic

Main drivers for ReplaceMagic (beside to fix your documents) were:

In case of any questions please do not hesitate to contact us.