Dealing with a “401 Unauthorized: Access Is Denied Due To Invalid Credentials” error can be incredibly frustrating. This error indicates that the request you have made is valid, but you do not have permission to access the resource you requested.
Specifically, a 401 error means that your credentials – usually a username and password – were rejected as invalid. There are a few common causes of a 401 unauthorized access denied error that are worth exploring when troubleshooting.
Read on to learn more about what this error means, why you may be seeing it, and most importantly, how to resolve a 401 unauthorized access denied error so you can get back to accessing the resources you need.
What Does a 401 Unauthorized Error Mean?
A 401 unauthorized error is an HTTP status code that means the credentials presented for authentication were invalid. This is different from a 403 forbidden error, which means the credentials were valid but the authenticated user does not have permission to access the specified resource.
With a 401 error, the request itself is perfectly valid and the resource being requested exists, but there is an issue with the username/password (or other credentials) that were provided. This results in the 401 unauthorized status code being returned, along with a message like “401 Unauthorized” or “401 Access Denied.”
Common Causes of a 401 Unauthorized Error
There are a few key reasons you may be seeing a 401 unauthorized access denied message:
Incorrect Username or Password
The most common trigger for a 401 error is typing in an incorrect username or password when attempting to access a login-protected resource. Double-check that the credentials you are providing match what you have set up for that account.
Accidentally entering an incorrect password, or mistyping your username, will often lead to a 401 error.
Expired Credentials
If you are utilizing temporary credentials or an expiring password, a 401 error may indicate that your login credentials have expired.
For example, many login systems require periodic password changes for security purposes. If your password has recently expired, entering your old (now invalid) password will produce a 401 error.
Application Misconfiguration
Less commonly, a 401 error can stem from an issue on the server side or an application misconfiguration.
For instance, the application may not be passing credentials correctly, authorization protocols may be misconfigured, or legacy systems may have outdated authentication setups.
These types of 401 triggers point to deeper technical problems beyond just entering incorrect credentials.
Insufficient Permissions
While a 401 error specifically means the provided credentials are invalid, a related 403 forbidden error can occur if the credentials are valid but lack the required permissions.
If you are definitively using the right credentials but still receive access-denied messages, it’s possible you do not have the correct access permissions assigned to your account.
How to Fix 401 Unauthorized: Access Is Denied Due To Invalid Credentials Error
When faced with a 401 unauthorized access denied error, there are a few steps you can take to troubleshoot and resolve the issue:
Double Check Your Credentials
First, carefully verify the username and password you are entering. Visual typos for usernames or passwords are a very common culprit.
If you have your credentials saved by your browser, double-check that the saved values match the actual login credentials for that account.
Also, try manually typing the username and password instead of using auto-fill just in case there is a mismatch.
Try Resetting Your Password
If you cannot determine what password you have set for the account, utilize the password reset function.
Most login systems allow you to reset your password through your email or phone number on file. Resetting your password generates a new valid credential that often resolves 401 errors.
Check for Expired Credentials
See if the service you are accessing utilizes expiring passwords or temporary access tokens. If your credentials have recently expired, this would cause a 401 unauthorized error.
Refreshing the credentials through password reset or regenerating access tokens can clear up 401 errors related to expiration.
Review Account Permissions
Check what level of access your account has for the application, resource, or API generating the 401 error. Certain interfaces require explicit permissions granted on a per-account basis.
Work with the owner or administrator of the system to review and expand your account permissions if needed.
Clear Cookies and Cache
Clearing your browser cookies and cache can clear up instances where you are being incorrectly logged out or denied access due to outdated token information.
After clearing cache/cookies, close and reopen your browser before attempting to log in again. This resets all active sessions and often resolves intermittent 401 unauthorized errors.
Contact Technical Support
For 401 errors that persist, technical troubleshooting with the owner of the application may be required. There could be an issue with credential passing, authentication protocols, or outdated systems resulting in the 401 error.
Logging error codes, replicating the 401 behavior across browsers and devices, and contacting technical support facilitates resolving these deeper issues.
401 Unauthorized Errors for APIs and Services
401 unauthorized errors commonly occur when interacting with APIs (application programming interfaces) and other machine-to-machine services like cloud platforms.
The same causes and fixes apply in these scenarios, but invalidating and regenerating access tokens is often required to resolve 401 API errors.
Regenerating API Keys and Access Tokens
Most modern APIs utilize generated API keys or JSON web tokens (JWTs) for authenticating clients and applications. A 401 error from an API typically means your access token or API key has been invalidated or expired.
Logging into the API dashboard to create a fresh key/token will resolve 401 errors in these cases. Be sure to update the new token in all the places it is programmatically utilized.
Double Checking Server Time
When generating time-sensitive JWTs, server time drift between the generating server and client-server can inadvertently invalidate tokens and cause 401 errors.
Check that server times are properly synced to avoid “not yet valid” type 401 errors related to engineered expiration times.
Updating SDKs/Libraries
Outdated SDK versions with broken authentication handling can lead to 401 errors for an otherwise valid access token.
Check API release notes for required SDK upgrades, and update client applications to the latest libraries and frameworks when troubleshooting.
Preventing 401 Unauthorized Errors
While 401 errors cannot always be avoided in complex authentication environments, the following tips can help minimize instances:
- Enforce Strong Password Policies: Require adequate password length, complexity, expirations, and logging to reduce incorrect credentials.
- Implement Multi-Factor Authentication: Adding factors like biometrics improves security and provides account recovery mechanisms.
- Audit API Keys and Tokens: Proactively scan access logs for expiring API credentials to renew before encountering 401s.
- Use OAuth 2.0/OIDC: Standard authentication protocols eliminate custom coding errors that lead to 401 failures.
- Monitor Token Expiry: Check for and refresh expiring tokens programmatically to avoid sudden 401 errors.
Conclusion
401 unauthorized errors due to invalid credentials can disrupt access to critical systems and data. By learning the common causes of 401 errors and following authentication best practices, companies can minimize credential-related access issues.
Proactively managing credentials, enabling multi-factor login, handling expiring tokens, and resolving 401 errors through password resets and access token regeneration will keep employees productive and customers satisfied.
