If an eligible rollover distribution is paid to you, 20% generally will be withheld for income tax. However, the full amount is treated as distributed to you even though you actually receive only 80%. You generally must include in income any part (including the part withheld) that you do not roll over within 60 days to another qualified retirement plan or to a traditional IRA.

If you are under age 59½ when a distribution is paid to you, you may have to pay a 10% tax (in addition to the regular income tax) on the taxable part (including any tax withheld) that you do not roll over.

If you don't have any more money to pull out except for interest, chances are you won't be able to pull that out

Many 401(k)s and IRAs only allow you to withdraw contributions. This can include your own money or an employer's, but earnings are protected. If you're still with the same employer, it will be difficult to get interest earned on investments out. So, if this is the case, then you probably won't be able to use the money. Look for another source.

The same difficulties apply to company contributions you're not fully vested in. You often need to work with an employer for a set number of years before you're fully entitled to their contributions. This money can be taken away or held until you've been with them long enough.

Finally, employment status may be causing your problem too. Some 401(k)s may be completely liquidated and closed if you're no longer employed. You're under much harsher conditions for getting access to the money, if you still have a job. You usually can only take limited withdrawals or loans, without being able to close out the account and get all of your money. It may not be fair, but this is the way it usually is under these circumstances.