Error: Failed to query available provider packages

TL;DR: tofu init is naming a provider that doesn't exist in the registry. Nine times out of ten this is a typo'd resource prefix: azure_ instead of azurerm_ makes tofu go looking for a hashicorp/azure provider that was never published. Fix the prefix (or the source in required_providers), then re-init.

Error: Failed to query available provider packages

Could not retrieve the list of available versions for provider
hashicorp/azure: provider registry.opentofu.org/hashicorp/azure was not
found

Steps

1. Read the provider name in the error. Ask: did you declare that provider? If not, find what implied it: grep -rn 'resource "azure_' . (swap in the prefix from your error). Expected: one or more resources with the wrong type prefix.

2. Fix the prefix, e.g. resource "azure_resource_group" becomes resource "azurerm_resource_group". Expected: the grep from step 1 finds nothing anymore.

3. If the provider IS declared, check required_providers for a typo'd source address. Expected: the source matches a real registry address, like hashicorp/azurerm.

4. Run tofu init. Expected: Initializing provider plugins... followed by - Installing hashicorp/azurerm v[...]....

When this applies

• tofu init fails naming a provider you never asked for, or a provider with a slightly-off name.
• Right after renaming resources or copying config between projects.

When it doesn't apply

• Error: Inconsistent dependency lock file is a lock mismatch; fix with tofu init -upgrade.
• Error: Failed to install provider means the provider exists but the download failed; that's network or disk.

Tool versions

All OpenTofu versions. Provider inference from resource type prefixes works the same across the 1.x line.

Why it happens

tofu infers required providers from resource type prefixes: anything starting azurerm_ implies the hashicorp/azurerm provider. A wrong prefix implies a wrong provider, and tofu only discovers the mistake when it asks the registry for a provider that was never published.

Edge cases

• If EVERY provider fails the same way at once, suspect network or proxy, not naming. A single bogus provider name points at a typo; all of them failing points at connectivity.
• Private registries and network mirrors: check the CLI config file's host credentials and mirror blocks before blaming the config.
• Modules can imply providers too. If the root config looks clean, grep inside .terraform/modules or your module sources for the bad prefix.

Stack Overflow question 79452956, 'OpenTofu fails to query provider packages': tofu init failed because a resource used the azure prefix instead of azurerm, so OpenTofu went looking for a nonexistent hashicorp/azure provider. The accepted answer (by Martin Atkins) identified the wrong resource type prefix as the cause, with the fix being to correct the prefix so tofu resolves the real provider. Source: https://stackoverflow.com/q/79452956/