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Summary: The content addresses recurring Outlook subfolder disappearance issues in Cached Exchange Mode, offering solutions like resetting mailbox settings and a professional OST to PST conversion tool for effective troubleshooting.

“I have relied on Outlook for as far back as I can recall. Its strong feature set and user-friendly interface have consistently made it my preferred email client. However, I’ve recently encountered some difficulties with it.

It felt like every attempt to access my emails in cached mode resulted in my Outlook subfolders mysteriously disappearing. After some research, I came across several suggested solutions, but unfortunately, none of them resolved the issue. Ultimately, I discovered the perfect solution to my problem.

After a few steps, I managed to pinpoint the root cause of the problem: one of my antivirus programs was triggering the issue. Once I disabled it, my subfolders reappeared in cached mode, and everything returned to normal.”

This issue can be caused by various factors and is quite common. Luckily, there are several solutions available to help you resolve it. Today, we will guide you through each of these solutions. Please read on attentively and begin the troubleshooting process now.

Subfolders Missing Issue in Cached Exchange Mode – Reasons to Know

  • One of the most common technical reasons for sub-folders going missing in Cached Exchange Mode is corruption in the .ost file. This can happen due to a wide range of reasons, like abruptly terminating an Outlook session while it is synchronizing with the Exchange server, power outages, system crashes, etc.
  • Another potential scenario is that the subfolder was unintentionally deleted from the Exchange Server. This can occur when someone with the appropriate permissions accidentally removes the folder or if the folder gets purged from the server during routine maintenance.
  • Another possible reason for this issue is a corrupted Outlook profile belonging to the user. This problem can manifest due to various causes, including an incomplete installation of Outlook or registry damage.
  • One of the most frequent causes of this problem is conflicts between other software and the Outlook application. This can encompass elements like antivirus programs or third-party utilities.
  • Finally, the last reason why sub-folders might be missing is that the necessary settings in Outlook have been disabled.
Subfolders Missing Issue in Cached Exchange Mode – Easy Solutions
1. Resetting the Mailbox Size Settings

In Outlook, you may face the issue of subfolders going missing from your mailbox when using Cached Exchange Mode. The main reason for this issue is that the size of your Offline Outlook Data File (OST) has exceeded the maximum size limit. When this happens, Outlook automatically removes the items in the mailbox folders so that they can stay within the size limit. To fix this problem, you need to check the mailbox size and then increase the maximum size limit for your OST file. Here’s how you can do it:

  • In Outlook, go to Account Settings and then tap on Account Settings again.go to Account Settings
  • Select your account and click Change
  • Here, you need to Keep the mail offline option to All.Keep the mail offline
  • Click Next and then OK if prompted.
  • Close the Account Settings window and restart Outlook.

After following these steps, your subfolders should reappear in Outlook, and you should no longer face this issue. All in all, you must have successfully configured Cached Exchange Mode & managed OST files.

2. Limiting the Number of Items per Folder

This problem may arise when a single folder contains an excessive number of items or when an excessive number of sub-folders are created. To address this issue, it is advisable for users to restrict the number of items in each folder to around 5000 and keep the number of sub-folders below 500. By adhering to these guidelines, users can help ensure that their data is effectively cached and synchronized, thereby preventing the occurrence of the ‘subfolders missing’ problem.

3. Disabling Cached Exchange Mode

Disabling Cached Exchange Mode can help fix many outlook issues, including Outlook not updating mail folders, the subfolder missing issue, etc. Follow these steps:

  • Access Microsoft Outlook & go to File > Account Settings.
  • Go to the account that you want to change and click Change.
  • Uncheck the box next to the option Use Cached Exchange Mode and click Next.
  • Click Finish and then Close.
  • Restart Microsoft Outlook and check if the issue has been resolved.
4. Enabling Shared Folders Download

By default, when you add a shared mailbox or public folder to your Folder Pane, only the primary message folders are downloaded to your computer. To view all the folders in a shared mailbox or public folder, you need to enable shared folder download. Follow these steps:

  • Access Outlook & click on File.
  • Click Account Settings, & then click Account Settings.
  • On the Email tab, double-click your Exchange account.
  • Click More Settings, and then click the Advanced tab.
  • Now, check the box next to Download Shared Folders.Download Shared Folders
  • Click Apply, then OK.

That’s it! Once you’ve completed these steps, the missing subfolders should reappear in your mailbox when viewed in Cached Exchange Mode.

5. Creating Sub-folders

If you are still stuck with this issue, you can try creating new subfolders to resolve it. To do this, follow the given steps:

  • Exit Outlook and restart it in Safe mode by holding down the CTRL key while you start Outlook.
  • Once Outlook starts, go to File > Open & Export > Import/Export.Import/Export
  • In the Import & Export Wizard, select Export to a file & then click Export to a file
  • Choose Personal Folder File (.pst) & tap Next.Choose Personal Folder File
  • Select the folder that you wish to export and then click Include Subfolders.
  • Enter the name for the exported file and then click Finish.
  • Now, open the exported PST file in Outlook, and you will see that all your subfolders are now visible. You can copy the contents of these folders to your original PST file and then delete the exported PST file.

Using a Professional Tool for Quick Resolution

As we know, this is a very common issue in that the Outlook Sub Folders are not appearing in cached mode. This problem generally occurs when the OST file of Outlook gets corrupted. In order to resolve this issue, you need to rebuild your OST file to PST by using Kernel for OST to PST Converter tool.

This software employs advanced algorithms to scan and repair damaged or corrupt OST files. After the scanning and repair process is completed, it reconstructs your entire mailbox data into new and healthy PST files, which can be effortlessly accessed through the Microsoft Outlook application. Additionally, this tool offers options for exporting the recovered mailbox data to various destinations, including Office 365, webmail services like Gmail and Yahoo Mail, as well as email servers such as Exchange Server, Novell GroupWise, and Lotus Domino Server.

Apart from fixing this problem, this software also provides various other features & options that can be used for managing or accessing your recovered mailbox data more effectively.

Final Say

These are among the most effective solutions to resolve the problem of Outlook subfolders not appearing in cached mode. Feel free to try these methods and determine which one resolves your issue. However, we recommend considering the use of the OST to PST tool for a speedy and efficient troubleshooting process.

If the problem continues to persist despite your best efforts, it might be advisable to seek professional assistance. With over a decade of experience in Outlook, our OST to PST tool can provide rapid and effective solutions to help you resolve this issue.

Kernel for OST to PST Converter