DOCUMENT:Q163017 09-AUG-2001 [crossnet] TITLE :Cannot Run Applications after Making File Association PRODUCT :Windows for Workgroups and Windows NT Networking Issues PROD/VER:winnt:4.0 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Workstation version 4.0 - Microsoft Windows NT Server version 4.0 ------------------------------------------------------------------------------- IMPORTANT: This article contains information about editing the registry. Before you edit the registry, make sure you understand how to restore it if a problem occurs. For information about how to do this, view the "Restoring the Registry" Help topic in Regedit.exe or the "Restoring a Registry Key" Help topic in Regedt32.exe. SYMPTOMS ======== By default, exe and .exe file extensions cannot be used in Windows NT 4.0 because they are reserved for running programs. However, the extension *.exe can be used as a valid file extension when creating a new application association. If you create an association with the *.exe extension, you will no longer be able to run applications or programs. CAUSE ===== The Add New File Type dialog box in Windows NT 4.0 allows for longer file extensions than Windows NT 3.51, which only allowed 4 characters. RESOLUTION ========== If the *.exe association has been made and/or removed, you can add the default .exe file type back by using Registry Editor. You can also use the Emergency Repair Disk to recover the registry information. WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. For information about how to edit the registry, view the "Changing Keys And Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it. If you are running Windows NT, you should also update your Emergency Repair Disk (ERD). 1. Start Registry Editor (Regedt32.exe), and select the following key: HKEY_CLASSES_ROOT on Local Machine 2. From the Edit menu, click Add Key. 3. In the Key Name box, type ".exe" (without the quotation marks) and then click OK. 4. Select the new .exe key. 5. From the Edit menu, click Add Value. 6. In the Value Name box, type "Content Type" (without the quotation marks). Select REG_SZ for Data Type, and then click OK. 7. In the String box, type "application/x-msdownload" (without the quotation marks) and then click OK. 8. From the Edit menu, click Add Value. 9. Leave the Value Name box blank. Select REG_SZ for Data Type, and then click OK. 10. In the String box, type "exefile" (without the quotation marks) and then click OK. 11. Exit Registry Editor. All application and program functionality should now be restored to its original state. STATUS ====== Microsoft has confirmed this to be a problem in Windows NT version 4.0. Additional query words: apps blue screen ====================================================================== Keywords : Technology : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400 Version : winnt:4.0 Issue type : kbbug ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.