自己画得一个实体，做静力线性分析时，出现下列ERROR#1237，求高手帮忙解决，非常感谢！

***********************************************************************
** **
** **
** OptiStruct 10.0 **
** **
** Design and Optimization Software **
** from Altair Engineering, Inc. **
** **
** **
** Windows XP Professional SP3 (Build 2600) WWW-4B46AD9643E **
** 2 CPU: Pentium(R) Dual-Core CPU T4300 @ 2.10GHz **
** CPU speed 2100 MHz **
** 1066 MB RAM, 3935 MB swap **
** **
** Build tag: 0466938_5333O00_Ci3242M-000 14000 **
************************************************************************
** COPYRIGHT (C) 1996-2009 Altair Engineering, Inc. **
** All Rights Reserved. Copyright notice does not imply publication. **
** Contains trade secrets of Altair Engineering, Inc. **
** Decompilation or disassembly of this software strictly prohibited. **
************************************************************************

*** OptiStruct defaults set from:
install config file: D:\Hyperworks10/hwsolvers/hwsolver.cfg

NOTE # 1929
Created RAM scratch area: total size 200 MB.

*** ERROR # 1237 ***
CQUAD4 element number 8039 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 8045 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 8048 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 8049 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 8050 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 8051 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9900 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9901 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9902 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9903 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9904 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9905 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9906 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9907 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9908 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9909 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9910 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9911 references
a missing or invalid property number 3.

*** ERROR # 1237 ***
CQUAD4 element number 9912 references
a missing or invalid property number 3.

*** More of ERROR messages # 1237 were suppressed...
*** ERROR # 14 ***
34 errors found in the input data.
************************************************************************
RESOURCE USAGE INFORMATION
--------------------------
MAXIMUM MEMORY USED 211 MB
THIS INCLUDES 200 MB RAMDISK AREA ALLOCATED IN MEMORY
MAXIMUM DISK SPACE USED 0 MB
************************************************************************
************************************************************************
COMPUTE TIME INFORMATION
------------------------
EXECUTION STARTED Sun May 20 17:17:29 2012
EXECUTION COMPLETED Sun May 20 17:17:29 2012
ELAPSED TIME 00:00:00
CPU TIME 00:00:00
************************************************************************
*** PROGRAM STOPPED: FATAL ERROR(s) ENCOUNTERED.
***** END OF REPORT *****

For Useful OptiStruct Tips and Tricks, go to the URL:
http://www.altairhyperworks.com/tips.aspx

************************************************************************
Following error/warning messages appeared too many times
and were suppressed:
1237
Total of 15 repeat error message(s) were suppressed.
To see more messages use "MSGLMT" control card in the data or config file.

************************************************************************
There were 34 error messages during input processing.
The first message is repeated below:
*** ERROR # 1237 ***
CQUAD4 element number 8039 references
a missing or invalid property number 3.