What causes "Content block with id [%s] not found" in siyuan-note/siyuan?

Run Settings - Rebuild index to resync blocktree.db against the .sy files.

Content block with id [%s] not found

Error message

Content block with id [%s] not found

What it means

Returned by GetHeadingDeleteTransaction. LoadTreeByBlockID(id) succeeded (the ID exists in the blocktree and its tree was found), but treenode.GetNodeInTree(tree, id) returned nil - the node is not present in the loaded tree. Conf.Language(15) is the localized 'Content block with id [%s] not found' template. This signals a desync between blocktree.db and the actual .sy content.

Source

Thrown at kernel/model/block.go:843

	if !sameTree {
		if err = indexWriteTreeUpsertQueue(defTree); err != nil {
			return
		}
	}
	FlushTxQueue()
	util.ReloadUI()
	return
}

func GetHeadingDeleteTransaction(id string) (transaction *Transaction, err error) {
	tree, err := LoadTreeByBlockID(id)
	if err != nil {
		return
	}

	node := treenode.GetNodeInTree(tree, id)
	if nil == node {
		err = fmt.Errorf(Conf.Language(15), id)
		return
	}

	if ast.NodeHeading != node.Type {
		return
	}

	var nodes []*ast.Node
	nodes = append(nodes, node)
	nodes = append(nodes, treenode.HeadingChildren(node)...)
	hiddenNodes := map[string]bool{}
	for _, hidden := range treenode.CollectFoldHiddenNodes(node.Parent) {
		hiddenNodes[hidden.ID] = true
	}

	transaction = &Transaction{}
	luteEngine := util.NewLute()
	for _, n := range nodes {

View on GitHub (pinned to 251596fc0d)

Solutions

Run Settings - Rebuild index to resync blocktree.db against the .sy files.
Verify the ID with an SQL query (SELECT * FROM blocks WHERE id = '<id>'); if absent, the block is gone and the action should be a no-op.
Reload the document in the editor to discard the stale block reference.
If reproducible, inspect the .sy file to confirm whether the heading node is actually missing.

Defensive patterns

Strategy: validation

Validate before calling

row, err := sql.QueryRow("SELECT root_id FROM blocks WHERE id = ?", id)
if err != nil || row == nil {
    // block does not exist; skip heading-delete
    return nil
}

Try / catch

tx, err := model.GetHeadingDeleteTransaction(id)
if err != nil && strings.Contains(err.Error(), Conf.Language(15)) {
    // block gone - rebuild index or surface stale-state to the user
    return nil
}

Prevention

Reload the document in the editor before issuing block-targeted operations.
Rebuild the index periodically on installations that sync heavily.
Verify block IDs against the blocks table before calling heading APIs.

When it happens

Trigger: Calling heading-delete on an ID whose blocktree entry points at a tree that no longer contains it; operating after a sync conflict that rewrote the .sy file; the heading was already deleted but the editor still holds the ID.

Common situations: Blocktree out of sync after manual .sy edits; data repo corruption; the block was moved to another tree and the blocktree lagged; frontend cached an outdated block list.

Related errors

AI-assisted analysis of siyuan-note/siyuan@251596fc0d (2026-08-12). Data as JSON: /api/errors/9b5fcfe33b85f7ce. Report an issue: GitHub.