Sometimes antivirus software flags legitimate DLLs as "False Positives" and moves them to quarantine. Check your security software’s history to see if it blocked the file and restore it if you trust the source.
Never trust a site that offers a single DLL download. Stick to official installers and system repair tools to keep your data safe. multitestps.dll Download
Which is giving you this error when you try to open it? Sometimes antivirus software flags legitimate DLLs as "False