# DateTamperingGracePeriod QLM can detect date tampering on a client's computer without an internet connection by comparing the current system date with the date the application last ran. The DateTamperingGracePeriod allows you to control how strict the algorithm should be when detecting date tampering. By default, the grace period is set to 1. To provide stricter control, you should set the grace period to 0. When QLM detects date tampering, which occurs when the user sets the date of the system back in time, the ValidateLicense APIs will return a date tampering error. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.soraco.co/docs/api-reference/.net-api/qlmlicense/properties/datetamperinggraceperiod.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.