Dear nek5000 users, I got the following error after merging two meshes. However, I don't understand the message. Is there any problem? What does it mean? Thank you very much. Regards, Simon Error message : 2773 2 4 Matrix: SELF!! 1 SELF!! 1189 1377 1189 1377 2 SELF!! 1360 1206 1360 1206 cont: SELF!! 2773 ?? ABORT: SELF-CHK 1 5 2773 0 Try to tighten the mesh tolerance! 3024 8 10 Matrix T: slfchk 3024 0 1 slfchk 2116 2275 2288 2133 2121 2276 2289 2138 2 slfchk 2275 2587 2574 2288 2276 2588 2575 2289 3 slfchk 2587 2821 2769 2574 2588 2822 2770 2575 4 slfchk 2821 2951 2912 2769 2822 2952 2913 2770 5 slfchk 2951 3120 3081 2912 2952 3121 3082 2913 6 slfchk 3120 3237 3224 3081 3121 3238 3225 3082 7 slfchk 3237 3302 3263 3224 3238 3303 3264 3225 8 slfchk 3302 3341 3289 3263 3303 3342 3290 3264 9 slfchk 3341 3354 3328 3289 3342 3355 3329 3290 10 slfchk 2133 2288 2301 2150 2138 2289 2302 2155 3024 this is nel in prexit