This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.1)

Troubleshooting on Windows

Passwords

If the front end password dialog box appears when you launch Mathematica, either Mathematica could not locate the mathpass file or there was no valid password in the mathpass file. To resolve this problem, first check that there is a mathpass file in one of these directories: $BaseDirectory\Licensing, $InstallationDirectory\Configuration\Licensing, or $UserBaseDirectory\Licensing. To find the exact location of these directories on your machine, evaluate the command $BaseDirectory (or $InstallationDirectory or $UserBaseDirectory) in a notebook. If you did not find a mathpass file in these locations, follow the instructions in "Entering a Single-Machine Password" to reenter your password.
If there is a mathpass file in one of those directories, the password or passwords are invalid. Make sure that your MathID number matches the MathID number used to issue your password. If your MathID number changes, you will need to contact Customer Service to get a new password. Contact information is provided in "Registration and Passwords".

Front End Preferences

Front end preferences, such as the locations of recently opened and saved files, are stored in a front end initialization file called init.m. This file is located in $UserBaseDirectory\FrontEnd. The default value of $UserBaseDirectory for different versions of Windows is listed in "Configuration Files on Windows". To find the exact location of this directory on your machine, evaluate the command $UserBaseDirectory in a notebook.
If you need to reset the front end preferences to their default values, hold down Shift+Ctrl during startup. This will cause the initialization file to be rebuilt automatically.

Caches

Information about your Mathematica system layout, such as the locations of text resource files, is stored in caches. These caches are located in C:\Windows\Local Settings\Application Data\Mathematica\FrontEnd\6.0 Caches\ on Windows Me/NT and in C:\Documents and Settings\username\Local Settings\Application Data\Mathematica\FrontEnd\6.0 Caches\ on Windows 2000/XP.
A corrupted cache may cause the front end to produce an error or quit immediately on startup. The most convenient way to restore the caches to their default values is to hold down Shift+Ctrl during startup. This will cause the Mathematica caches and the initialization file to be rebuilt automatically. If you want to rebuild your caches but retain your preferences, hold down Shift during startup. This will delete and rebuild the cache without rebuilding your front end initialization file.

Technical Support

For further assistance, check the Technical Support FAQs on the web at support.wolfram.com. If you do not find the information you need, please contact Technical Support by sending email to support@wolfram.com or by calling +1-217-398-6500. Include your license number in all correspondence. Your license number is printed on your license certificate. It is also available after installation by going to the Help menu and clicking About Mathematica. You must be a registered customer in order to receive installation support. You must have a current Premier Service subscription to receive Technical Support.