Você pode tentar um destes:
Método 1
Rename your rules to a shorter name. To rename a rule in Outlook, follow these steps.
For Outlook 2010 and later versions:
1.On the File tab, click Info.
2.Then, click Manage Rules and Alerts.
3.On the E-mail Rules tab, click the rule that you want to rename.
4.Click Change Rules, and then click Rename Rule.
5.Type a new, shorter name for the rule, and then click OK.
6.Click OK to close the Rules and Alerts dialog box.
Para o Outlook 2007 e o Outlook 2003:
1.On the Tools menu, click Rules and Alerts.
2.On the E-mail Rules tab, click the rule that you want to rename.
3.In the Change Rule list, click Rename Rule.
4.Type a new, shorter name for the rule, and then click OK.
5.Click OK to close the Rules and Alerts dialog box.
Método 2
Delete any old rules. To delete a rule in Outlook, follow these steps:
Para o Outlook 2010 e versões posteriores:
1.On the File tab, click Info.
2.Then, click Manage Rules and Alerts.
3.On the E-mail Rules tab, click the rule that you want to rename.
4.Click the Delete button, and then click Yes to confirm the deletion.
5.Click OK to close the Rules and Alerts dialog box.
Para o Outlook 2007 e o Outlook 2003:
1.On the Tools menu, click Rules and Alerts.
2.On the E-mail Rules tab, click the rule that you want to delete.
3.Click Delete, and then click Yes to confirm the deletion.
4.Click OK to close the Rules and Alerts dialog box.
Método 3
Combine similar rules to reduce the overall size of your rules. If it is possible, combine similar rules to reduce the overall size of your rules. After you have combined similar rules, delete the rules that you do not need any more. To edit an existing rule in Outlook, follow these steps.
Para o Outlook 2010 e versões posteriores:
1.On the File tab, click Info.
2.Then, click Manage Rules and Alerts.
3.On the E-mail Rules tab, click the rule that you want to rename.
4.Click Change Rule, and then click Edit Rule Settings.
5.Modify the rule as appropriate.
6.Click OK to close the Rules and Alerts dialog box.
Para o Outlook 2007 e o Outlook 2003:
1.On the Tools menu, click Rules and Alerts.
2.On the E-mail Rules tab, click the rule that you want to edit.
3.In the Change Rule list, click Edit Rule Settings.
Modify the rule as appropriate.
4.When you are finished, click Finish, and then click OK to close the Rules and Alerts dialog box.
Note If the rule is a client-only rule, you must click OK two times to close the Rules and Alerts dialog box.
Método 4
Move your personal folders (.pst) file to a location that has the shortest path name. If you have rules that move e-mail messages to a .pst file, move your .pst file to a location that has the shortest path name as possible. For example, move your .pst file to a location such as C:\file_name.pst. To move your .pst file in Outlook, follow these steps:
1.In the Navigation Pane, right-click Personal Folders or the folder name that appears for your .pst file, and then click Properties for folder_name.
Note This folder will always be a top-level folder in the Navigation Pane, in Mail.
2.Na guia Geral, clique em Avançado.
3.Na caixa de texto Nome do arquivo, anote o caminho completo e o nome do arquivo .pst.
4. Clique duas vezes em OK para fechar a caixa de diálogo Propriedades do folder_name.
5.Quit Outlook.
6.Use Microsoft Windows Explorer para mover o arquivo .pst para o novo local.
Note By default, the location for a .pst file is the drive:\Documents and Settings\user_name\Local Settings\Application Data\Microsoft\Outlook folder. The default location is a hidden folder. To use Windows Explorer to locate this folder, you must first turn on the display of hidden folders. To do this, follow these steps:
a.In Windows Explorer, click Folder Options on the Tools menu.
b.Click the View tab.
c.In the Advanced Settings section, click Show hidden files and folders under Hidden files and folders.
d.If you want to see all file name extensions, click to clear the Hide extensions for known file types check box under Files and Folders.
Note that hidden folders appear dimmed to indicate they are not typical folders.
e.Clique em OK.
7.Use um dos seguintes métodos para abrir o item de email no Painel de Controle:
To do this on a Windows XP-based computer or on a Windows Server 2003-based computer, click Start, click Control Panel, click User Accounts, and then click Mail.
Note If you are using the Classic view, click Start, click Control Panel, and then double-click Mail.
Para fazer isso em um computador com Microsoft Windows 2000, clique em Iniciar, aponte para configurações, clique em Painel de controle e, em seguida, clique duas vezes em email.
8.Clique em Mostrar perfis e clique no perfil que contém seu arquivo .pst.
9.Clique em Propriedades e, em seguida, clique em Arquivos de Dados.
10.Clique no arquivo de dados .pst que você moveu e clique em Configurações.
11.Quando você for solicitado a informar que o arquivo de dados não foi encontrado no local antigo, clique em OK.
12.Locate e, em seguida, clique no arquivo .pst no novo local da pasta e clique em Abrir.
13. Clique em OK e, em seguida, clique em Fechar duas vezes.
14. Clique em OK.
15. Painel de Controle de Qualidade.
16. Reinicie o Outlook.
Método 5
Clear the on this machine only check box. If you use a rule to move e-mail messages to a .pst file, click to clear the on this machine only check box unless you are accessing your Exchange Server e-mail from different client computers. To do this in Outlook, follow these steps:
Para o Outlook 2010 e versões posteriores:
1.On the File tab, click Info.
2.Then, click Manage Rules and Alerts.
3.On the E-mail Rules tab, click the rule that you want to rename.
4.Click Change Rule, and then click Edit Rule Settings.
5.Click to clear the On this machine only check box if the check box is selected.
6.Complete the Rules Wizard. Click OK to close the Rules and Alerts dialog box.
Para o Outlook 2007 e o Outlook 2003:
1.On the Tools menu, click Rules and Alerts.
2.On the E-mail Rules tab, click the rule that you want to edit.
3.In the Change Rule list, click Edit Rule Settings.
4.If selected, click to clear the on this machine only check box.
5.Complete the Rules Wizard.
6.Click OK to close the Rules and Alerts dialog box.
Note If you use client-only rules that point to local resource files, for example moving items to a folder in a .pst file, and you use multiple computers to access Microsoft Outlook, rule conflicts may occur. Therefore, some client-only rules may be disabled.
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da Microsoft