Answer
Confirm the folder where Report Designer itself is installed is genuinely writable for the currently logged-in Windows user, checking that neither the folder nor its files are marked read-only. Separately, confirm the folder where the report layout file itself is being saved has the same writable permissions. A save error when adding an image commonly traces back to insufficient filesystem write permissions on one of these two specific locations, rather than an actual Report Designer bug or a genuinely incorrect image path setting.