问：用/seg是提示Error on avi stream write,怎么回事？

whosru

想把几个静态分析的结果保存到一个avi里面，用/seg提示Error on avi stream write，最后只能看到最后一部的图片，不知道什么问题，麻烦各位了。

顺便问下：瞬态分析中，每个载荷步过程中可不可以在/prep7中修改模型？

动画问题命令流：
/prep7  
et,1,53,,,1
mp,murx,1,1
mp,murx,2,1
mp,murx,3,1000  
mp,murx,4,1000  
mp,rsvx,2,1e-7  
mp,mgxx,4,100   
rect,,.1,-.1,.5
rect,.05,.09,.15,.35
aovlap,all  
rect,.1,.35,,.4
rect,.11,.13,.13,.2
rect,.11,.25,.05,.24
rect,.13,.23,.07,.22
asel,s,loc,x,.1,.35
aovlap,all  
asel,all
/pnum,area,1
aplot   
aadd,4,9
numcmp,area
aplot   
asel,s,area,,1,3,2  
aatt,1,,1   
asel,s,area,,2  
aatt,4,,1   
asel,s,area,,4  
aatt,2,,1   
asel,s,area,,5  
aatt,3,,1   
asel,s,loc,x,,.1
aesize,all,0.015
asel,s,loc,x,.1,.35
aesize,all,0.01
asel,all
amesh,all   
asel,s,loc,x,,.1
esla,s  
cm,left,elem
esel,s,mat,,4   
cm,iron,elem
asel,s,loc,x,.1,.35
esla,s  
cm,right,elem   
nsle,s  
nsel,r,loc,x,.1
cm,mid,node
cmsel,s,mid
cmsel,a,left
ceintf,0.25,az  
nsel,s,ext  
nsel,r,loc,x,0.1
nsel,r,loc,y,0.005,0.395
cm,mi,node  
nsel,s,ext  
cmsel,u,mi  
d,all,az
allsel,all  
FMAGBC,'IRON'   
esel,s,mat,,2   
BFE,P51X,JS,1, , ,100000, ,
allsel,all
/solu
magsolv
/post1
plf2d
/seg,dele
/seg,dele
/seg,multi,file,0.1
*do,i,1,4
/prep7
allsel
cedel,all,,,any
cmdel,mi3
allsel
asel,s,loc,x,,0.1
agen,,all,,,,-0.01,,,,1
allsel
cmsel,s,mid
cmsel,a,left
ceintf,0.25,az
allsel
nsel,s,ext
nsel,r,loc,x,0.1
nsel,r,loc,y,0.005,0.395
cm,mi3,node
alslel
nsel,s,ext
cmsel,u,mi3
d,all,az
allsel
/solu
magsolv
/post1
plf2d
*enddo
/seg,off
/anfile,save,file,avi
anim,1