---
title: Why Some Data are not Recovered?
description: "[Microsoft has set a limit on the PST/OST file size](https://docs.microsoft.com/en-us/outlook/troubleshoot/data-files/file-size-limits-of-pst-and-ost-files-are-larger). So, please check if the output PST file size is close to that limit. If yes, then there are two solutions: 1. [Split the output file into several smaller ones](https://www.datanumen.com/outlook-repair-split/).…"
url: "https://www.datanumen.com/knowledgebase/why-some-data-are-not-recovered/"
updated: "2022-01-14"
category: Using Products / DataNumen Outlook Repair/Exchange Recovery
---

# Why Some Data are not Recovered?

[Microsoft has set a limit on the PST/OST file size](https://docs.microsoft.com/en-us/outlook/troubleshoot/data-files/file-size-limits-of-pst-and-ost-files-are-larger). So, please check if the output PST file size is close to that limit. If yes, then there are two solutions:

1. [Split the output file into several smaller ones](https://www.datanumen.com/outlook-repair-split/). This is the recommended method.
2. [Increase the size limit according to Microsoft document](https://support.microsoft.com/en-us/topic/how-to-configure-the-size-limit-for-both-pst-and-ost-files-in-outlook-2f13f558-d40e-9c2a-e3b6-02806fa535f4). However, there are some errors in the document and the operation may not always succeed.