The server does not recognized the request method.
- Virus or Malware: it is not the server who get infected, instead it is your actual internet browser. The level of an attack can render your browser corrupted, or in worst case scenario, a virus can completely overtake and control the browser
- Server overload: a relatively moderate website goes viral with a post ad thousands of visitors turns into hundreds of thousands or even millions.
- Server error: actual server is unable to appropriately respond to an end-user browser request
- Expired server software: least likely, especially in cheap hosting providers, server upgrades may occur in a timely taken.
Step 1: Perform A Deep-level Virus Scan
Confirm your antivirus software features is the latest version and has the latest identification and quarantine technology
Step 2: Clear Browser/ Internet Cache
Persistent code is due to an old or corrupted files stored by your web browser cache. This can occur when you recently had made a significant infrastructure changes to the backend of the website.
Step 3: Disable Proxy Settings
If you use proxy settings then this maybe is the reason for you to have error 501. To determine it, you need to navigate into your proxy settings and disable the proxy server. Restart your computer and try again.
Step 4: Contact NET
Contact the technical support team and inform them the situation.