I create a new web app or try a remove a old web app and I get this error: Value cannot be null. Parameter name: str at System.Security.Permissions.FileIOPermission.HasIllegalCharacters(String[] str) at System.Security.Permissions.FileIOPermission.AddPathList(FileIOPermissionAccess access, AccessControlActions control, String[] pathListOrig, Boolean checkForDuplicates, Boolean needFullPath, Boolean copyPathList) at System.Security.Permissions.FileIOPermission..ctor(FileIOPermissionAccess access, String path) at Microsoft.SharePoint.Administration.SPIisSettings.get_Path() at Microsoft.SharePoint.Administration.SPWebApplication.CreateDefaultInstance(SPWebService service, Guid id, String applicationPoolId, IdentityType identityType, String applicationPoolUsername, SecureString applicationPoolPassword, String iisServerComment, Boolean secureSocketsLayer, String iisHostHeader, Int32 iisPort, Boolean iisAllowAnonymous, DirectoryInfo iisRootDirectory, Uri defaultZoneUri, Boolean iisEnsureNTLM, Boolean createDatabase, String databaseServer, String databaseName, String databaseUsername, String databasePassword, SPSearchServiceInstance searchServiceInstance, Boolean isPaired, Boolean autoActivateFeatures) at Microsoft.SharePoint.ApplicationPages.ExtendVirtualServerPage.BtnSubmit_Click(Object sender, EventArgs e) at System.Web.UI.WebControls.Button.OnClick(EventArgs e) at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) Troubleshoot issues with Windows SharePoint Services.

Hi GGratto, Thanks for your question. What permission do you have when you try to create a web application? Did you select “delete content database” and “delete IIS web site” when you try to delete the web application? What is your MOSS 2007 version? Can you create or delete web application before? How did you input the parameters when you create the web application? Follow the following link, make sure you input the correct parameters, then check the effect. Create or extend Web applications http://technet.microsoft.com/en-us/library/cc262668(office.12).aspx If the issue still persists, select Administration category and enable diagnostic log, reproduce the issue, collect the SharePoint event and trace log and post the error information into the forum. By default trace logs are under C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\LOGS. Please collect the latest trace log. Open Event Viewer, find the latest event log about SharePoint. Post them into the forum. For more information about how to configure ULS logging, please refer to the following article: Configure diagnostic logging settings http://technet.microsoft.com/en-us/library/cc262714.aspx Regards, Rock Wang Microsoft Online Community Support

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