When Telegram says "this group is no longer accessible," it means that the group you are trying to access has been closed, deleted, or made private by the group administrator or the owner of the group. There are several possible reasons why a group may become inaccessible:

Group Deletion: The group administrator or owner may have decided to delete the group permanently. Once a group is deleted, it cannot be restored, and all its content, messages, and members are removed.
Group Closure: The group administrator or owner may have chosen to close the group temporarily. This means that while the group still exists, it is not currently accessible to its members. Closure could be due to various reasons, such as maintenance, restructuring, or taking a break from group activities.
Privatization: The group may have been converted from a public or open group to a private group. In this case, only invited members can access and participate in the group's discussions and content. Non-members or previous members may receive the "no longer accessible" message if they try to access the group without an invitation or if they were removed from the group.
Revocation of Link or Invitation: If a group previously allowed joining via a public link or invitation, the administrator or owner may have revoked the link or invitation, rendering it invalid. As a result, attempting to join the group using the expired link or invitation will result in the "no longer accessible" message.
Administrative Action: The group administrator or owner might have taken specific administrative actions, such as restricting access to the group or blocking certain members, which could lead to the group becoming inaccessible for those affected.
It's important to note that the specific reason for a group becoming inaccessible can only be determined by the group administrator or owner. They have control over the group's settings and can decide to modify or limit access as they see fit. If you encounter this message, it's recommended to reach out to the group administrator or owner for more information on the status of the group and any potential changes that have been made.
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