Error: Failed to connect the specified server. Server library could not be loaded

Error Message

When using direct connect with ArcSDE on a 64-bit operating system, the following error message is encountered:

"Failed to connect the specified server. Server library could not be loaded."


Because ArcGIS Desktop is a 32-bit application, it cannot work with applications created with 64-bit operating system libraries.

Solution or Workaround

Select one of the two solutions described below.

  • Uninstall the Oracle Net Client 64-bit version and install the Oracle Net Client 32-bit version on the 64-bit operating system. Also, ensure the Oracle Net Client's full version matches the Oracle database's full version (for example,
  • If ArcGIS for Desktop and ArcSDE are on the same 64–bit operating system, have the Oracle 32-bit client home as the first entry in the PATH variable.


    PATH=C:\Oracle\product\11.2.0\client_32\bin; C:\Oracle\product\11.2.0\client_64\bin;��

    In ArcGIS 10.1, the direct connection can be made using Oracle Instant Client. It does not require an Administrative Client as required in ArcGIS 9.3.1 and 10.0. See the ArcGIS Help under Related Information for more information.

Related Information