How to Fix Plugin or Theme Upload/Update 500 Errors on OpenLiteSpeed Servers With xCloud

Updated May 13, 2026 · 2 min read

When a WordPress site on an OpenLiteSpeed (OLS) server fails while uploading or updating a plugin/theme, the issue may be related to incorrect ownership of OpenLiteSpeed temporary files.

This guide explains how to identify the issue and apply the known fix.

Symptoms

A customer may report one or more of the following:

Plugin upload fails
Plugin update fails
Theme upload fails
Theme update fails
WordPress shows a 500 Internal Server Error
The issue happens during upload/update actions only
The site is hosted on an OpenLiteSpeed / OLS stack server

Example customer message:

I cannot update the theme. It is showing a 500 error on your server

Affected Stack

This issue is related to servers using the OpenLiteSpeed (OLS) stack.

It does not usually happen on NGINX stack servers.

In customer-friendly language:

Your server is using the OpenLiteSpeed stack. This issue is related to OpenLiteSpeed temporary file handling and is not related to Redis or cache settings.

Error to Look For

Open the server logs in xCloud:

Server → Logs

Or use the direct server logs URL:

Copy

https://app.xcloud.host/server/{server_id}/logs

Look for this error:

Failed to obtain or reinitialize VMemBuf.

Example:

2026-05-13 06:27:02.750619 [ERROR] [269567] [192.128.217.123:13925:H2-1]

Failed to obtain or reinitialize VMemBuf.

If this error appears while the customer is uploading or updating a plugin/theme, apply the fix below.

Likely Cause

OpenLiteSpeed uses temporary swap/report files under:

/tmp/lshttpd/

In some cases, these files or folders may have incorrect ownership. When OpenLiteSpeed cannot write to or reinitialize these temporary buffers properly, WordPress actions such as plugin/theme upload or update can fail with a 500 error.

The fix is to restore ownership to the correct server user:

xcloud:xcloud

Fix

SSH into the server or use the xCloud Command Runner.

Run:

📄

filename.js

Copy

chown -R xcloud:xcloud /tmp/lshttpd/swap

chown -R xcloud:xcloud /tmp/lshttpd/.rtreport*

Using xCloud Command Runner

If you are using the xCloud dashboard:

1. Open the xCloud dashboard.

2. Go to Servers.

3. Select the affected server.

4. Open Command Runner.

5. Run the following commands:

chown -R xcloud:xcloud /tmp/lshttpd/swap

chown -R xcloud:xcloud /tmp/lshttpd/.rtreport*

6. Wait for the command to finish.

7. Ask the customer to test the plugin/theme upload or update again.

Verification

After applying the fix, ask the customer to retry the same action:

– Upload the plugin again

If successful, the issue is resolved.

Also, check the server logs again and confirm that the same error is no longer appearing during the upload/update attempt: