# Errors "Failed to login - null" or "Failed to login - invalid session" when joining a server

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#### **Issue description**

These errors mostly happen when there is a Microsoft account autentication issue on your Launcher, whether it is Technic or CurseForge.

<table border="1" id="bkmrk--1" style="border-collapse: collapse; width: 115.926%; height: 283px; border-width: 0px;"><colgroup><col style="width: 50.0618%;"></col><col style="width: 50.0618%;"></col></colgroup><tbody><tr><td style="border-width: 0px;">[![image.png](https://siriusmc-bookstack.s3.eu-west-1.amazonaws.com/uploads/images/gallery/2024-01/scaled-1680-/DlmnjQ2HxQdVsKMn-image.png)](https://siriusmc-bookstack.s3.eu-west-1.amazonaws.com/uploads/images/gallery/2024-01/DlmnjQ2HxQdVsKMn-image.png)</td><td style="border-width: 0px;">[![image.png](https://siriusmc-bookstack.s3.eu-west-1.amazonaws.com/uploads/images/gallery/2024-01/WtZSfmsfgxFRFs1w-image.png)](https://siriusmc-bookstack.s3.eu-west-1.amazonaws.com/uploads/images/gallery/2024-01/WtZSfmsfgxFRFs1w-image.png)</td></tr></tbody></table>

#### **Solution**

Closing the game and launcher completely, logging out from the launcher and relogging back would be the most common fixes, but if that still doesn't work, you can access '%appdata%/roaming/.technic' and delete the 'oauth' folder.

If this still doesn't solve it, you can open a support ticket on our Discord server.