Trouble With Task Scheduling

Enabling Scheduled Tasks Without a Password

When you try to schedule a routine task on Windows XP, the system often reports that the task “did not run because an incorrect password or user name was used.” This happens because, by default, XP restricts scheduled tasks that run under accounts with blank passwords to console logon only. If you want a task - like Disk Cleanup - to launch automatically when the machine is idle or when the user logs on, you must lift this restriction. The solution is two‑fold: adjust the Local Security Policy on a Professional or higher edition, or apply a registry tweak for Home editions.

First, open the Local Security Policy editor. Click Start, choose Control Panel, then Administrative Tools, and double‑click Local Security Policy. In the left pane, expand Local Policies and click Security Options. Locate the policy named “Accounts: Limit local account use of blank passwords to console logon only.” By default this is enabled. Double‑click the policy, set it to Disabled, and click Apply. Once disabled, any scheduled task can run under a local account even if that account’s password is blank, as long as the task’s trigger is set to “At log on” or “On idle.” This change does not affect the security of other accounts; it merely allows the system to honor scheduled tasks without prompting for credentials.

For XP Home users, the Local Security Policy console is not available. In that case, a small registry edit does the same job. Press Win + R, type regedit, and hit Enter. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa. Create a new DWORD (32‑bit) Value named BlankPasswordNotAllowed. Set its value data to 0. If the value already exists, change it to 0. This flag tells the system to treat blank passwords as valid for scheduled tasks. The registry change takes effect after a reboot or by restarting the Task Scheduler service.

After the policy or registry tweak is in place, create the Disk Cleanup task. Open Task Scheduler, click Create Task, name it “DiskCleanupIdle,” and set the trigger to “On idle” or “At log on.” Under Actions, browse to C:\Windows\System32\cleanmgr.exe, and add any desired arguments such as /sagerun:1 to pre‑define the cleanup options. On the Conditions tab, check “Start the task only if the computer is idle for” and specify a suitable idle time. If you also want the task to run at log on, add a second trigger. Because the account used by the task now has no password requirement, the task will launch without prompting for credentials.

When the task first runs, it may show a dialog asking for confirmation. This can be suppressed by selecting the “Run whether user is logged on or not” option and checking “Do not store password.” The task will then execute silently in the background. Verify its success by looking at the History tab of the task or by inspecting the Event Viewer for a successful task completion message. If you still see the password error, double‑check that the account you selected is a local user with a blank password and that the task’s security options are set to “Run with highest privileges.” Once these steps are confirmed, the Disk Cleanup will run automatically whenever the system is idle or when the user logs on, freeing you from manual maintenance.

Stopping the Automatic Compression of Files

In many XP installations, a feature called “Compress old files” creates a hidden folder that can accumulate a huge amount of data - often tens of thousands of entries - without obvious prompts. Jim’s wife reported that her “compress files” area filled with 32,000 or more items daily. This not only wastes disk space but also slows down file operations. Removing the check that triggers this compression is straightforward but requires a registry tweak that disables the feature entirely.

The easiest route is to download a ready‑made .reg file from a reputable source and import it into the registry. One such file can be found at http://www2.whidbey.com/djdenham/DeleteOldFiles.htm, a site that has long supplied XP utilities. Save the file to the desktop, double‑click it, and confirm the registry update when prompted. The tweak removes the flag that tells Windows to compress files older than a certain threshold, effectively disabling the entire background compression process. After the import, reboot the computer or restart the Windows Explorer process to ensure the changes take effect.