diff --git a/lib/model/model.go b/lib/model/model.go
index 13da913b2..b4ee3925e 100644
--- a/lib/model/model.go
+++ b/lib/model/model.go
@@ -2561,7 +2561,7 @@ func (m *model) DelayScan(folder string, next time.Duration) {
 func (m *model) numHashers(folder string) int {
 	m.mut.RLock()
 	folderCfg := m.folderCfgs[folder]
-	numFolders := len(m.folderCfgs)
+	numFolders := max(1, len(m.folderCfgs))
 	m.mut.RUnlock()
 
 	if folderCfg.Hashers > 0 {