No, when you go from a domain to a workgroup, the domain account will stop working and the only way to fix this short of reinstalling Windows is to put the machine back on the domain long enough to create a local user account.
Frankly, I know it happens all the time, but companies should not be allowing employees to buy and take home decommissioned computers that have not had the HDD formatted. Odds are there's other software on that computer, licensed to the company, which is not authorized for use in a home setting and your company could be in some serious legal trouble if this was discovered. So maybe the best thing you could do is just take the computer back to work with you one day and let the IT department have a chance to scrub it of all the software licensed only for use in the workplace and any other proprietary data they probably wouldn't want being outside the direct control of the company. They can also set you up with a local account so when they remove it from the domain it doesn't keep you from logging in.
I changed domains from a work domain to MSHOME domain. Now my user name and password do not work to get logged into Windows. Is there a way to revert back to the work domain somehow, and get logged back in?

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