Prevent and Fix Mozilla Error

Mozilla® Firefox® is a web browser unlike others that provides an interface that is easy to use and features, which enable the user to get information while surfing the web.


A number of error messages appear while using Mozilla® browsers especially the Java™ related issues like Firefox® unable to start, Firefox® is already running but not responding and "the program must close to allow a previous installation attempt to complete".




  • Reasons for the error: "Program must close to allow a previous installation attempt to complete"

  • Delete the system file 'xpicleanup.dat' to fix the error


Reasons for the error: "Program must close to allow a previous installation attempt to complete"


This type of error occurs mostly in Windows® operating systems when a particular system file 'xpicleanup.dat' is not deleted. This error is of utmost importance as it will alert you on the issues at hand and you will get to know the reason why such errors occur.



  • Sudden power cut


    A sudden power cut can be detrimental as it may result to a system crash or loss of vital data. This will happen when the user does not have a UPS or it’s just simply dysfunctional.




  • System upgrade was interrupted
    Software upgrade within the system is of utmost significance as it provides one with patches that seals loop holes in current system and application programs installed. An incomplete installation can result in programs not running as required thus the owner will be compelled to re-run the previous installation for a software upgrade to complete. This helps the user to clear all other previously downloaded items creating more disk space.


Delete the system file 'xpicleanup.dat' to fix the error



There is no need to panic when such errors occur as is the case for some users. It’s not a system error or a virus attack in your PC. All you have to do is simply locate the Mozilla® folder. The steps below are of help depending on Windows® operating system version.




  • Windows® XP

    Click the Start button on the left hand side of the task bar and on the pop-up menu, click on Search. In the pop-up window, click on the files and folders option that appear on the left. Click on the more advanced options list and check Search system folders, Search hidden files and folders, and Search sub folder option. In the field name box, type xpicleanup.dat. Click Search to start tracing the file. The right part of the window will display search results. Delete the file and restart Firefox®.


    Alternatively, on the task bar, click the Start button and on the popup menu click run and in the pop-up window type C:Program FilesMozilla Firefox and delete the xpicleanup.exe file.


  • Windows Vista® and Windows® 7


    Click the start button on the left hand side of the task bar and on the pop-up menu click on Search.In the search window type %APPDATA% and press the enter key. A folder window will appear. Delete the file xpicleanup.dat and restart Firefox now. Make sure Firefox® is not running when you do this.


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