QuickBooks error code 3371 occurs when QuickBooks is not able to load the license data and it appears on the screen with status code – 11118 or status code – 1. The primary causes behind QuickBooks error 3371 are a damaged QBregistration.dat file, the unexecuted Microsoft MSXML, or the license data cannot be retrieved or validated. The QBregistration.dat file needs to be executed every time the QuickBooks accounting software is activated and if unavailable then it leads to error 3371. Here are the steps that can be taken to eliminate QB error code 3371. 1. Firstly, you can try to reinstall EntitlementDataStore.ECML file which can be found under the Intuit ProgramData folder. Once you locate the file, delete it and reopen the QuickBooks. After that, you can follow the instructions to re-register QuickBooks. 2. The next measure is to update your Windows manually. Click the search bar on your system, write Check for Updates, and hit Enter. Now if any recent update is available then install it on the system. You might be prompted to execute a basic reinstall of QuickBooks.