Siemens Industry Online Support
Siemens AG
Entry type: FAQ Entry ID: 10208766, Entry date: 05/17/2021

How do you clear message "An OLE error has occurred”?

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The following provides information and remedies if you receive the message "An OLE error has occurred” when opening blocks or starting functions in STEP 7 or in option packages.

The message "An OLE error has occurred" is displayed, for example, when opening blocks or starting functions STEP 7 or the options packages if the start of a Windows application has failed.

OLE (Object Link Embedding) is a central Windows mechanism that is used internally when starting applications.

This error can have very different causes, for example incorrect installation or incorrect registry entries or even corrupt Windows programs in STEP 7 or STEP 7 projects in the Windows system.

1. Settings of the virtual memory

Check the space on the hard disk. You need at least 1 to 2 GB of free memory for STEP 7 V5.6.

Set the virtual memory in MS Windows to "Custom size" and enter the values for "Initial size" and "Maximum size". Further information and instructions for changing the virtual memory settings in MS Windows are available in Entry ID: 20440472.

2. Missing option package

Check in your STEP 7 project with which option packages the project was created and which option packages are missing in STEP 7 to continue processing the project. Information about this is available in Entry ID: 18631373.

3. Corrupt STEP 7 project

In some cases, your STEP 7 project may also be corrupted if the above message appears only for that one project. Make a copy of your project with the "Save as..." function and the option "With reorganization (slow)". Also check whether there is enough space on the hard disk or drive on which you want to save the STEP 7 project.

If execution of the "Save as..." function together with the "With reorganization (slow)" option is not successful, then do the reorganization manually. Create a new project and copy one object at a time from the corrupted project into the new project. If you cannot copy an object, try to save the data in it by creating and exporting a source for the object. Then import the source into the newly created project.

4. Incorrect installation

We recommend that you check the installed software products. It is possible that individual versions are not compatible with each other. The Compatibility Tool from Siemens is a function provided by the Industry Online Support with which you can select compatible software products or check the compatibility of existing configurations. More information is available in Entry ID: 64847781.

The installation could also be corrupted, for example because something was deleted in the installation directory. In this case, we recommend that you do a repair installation of STEP 7.

5. Missing or corrupted entries in the Registry

The following reasons may be responsible here:
  • A DLL file in the file system is corrupted (due to a copy error, for example) and therefore cannot be loaded.
  • A DLL file is missing (due to an unsuccessful installation, for example).
  • The Registry entry used to find a DLL file is incorrect (due to an unsuccessful over-installation, for example).

Do not make any changes to the Windows file system and Registry. In all three cases, we recommend a repair installation or reinstallation.

In some cases, incorrect Registry entries cannot be fixed even with a repair installation or reinstallation,
if, for example, the missing DLL file is a Windows DLL file from the "Windows > System32" directory. In this case, we recommend that you format the hard disk or partition from where the internal OLE error originates. But formatting will delete all data on the partition and so you should backup all data you still need beforehand.

If you have further questions and want to contact Technical Support, we need the diagnostics and system information from your PC.

Further Information
More information about collecting the diagnostics and system information and how you can send this data to Technical Support is available in Entry ID: 65976201.

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