Hello Marine,
You are trying to run a simulation in parallel. The boundary conditions file is then partitionned with partel program. You seem to run a version 6.0 of Telemac-2D, do you?
If yes, if your mesh has too many nodes (say more than 1,000,000), partel was not able to deal with so many nodes in version 6.0. This limitation has been corrected since version 6.2.
To be sure that it was your case, can you try to run this simulation in serial mode (PROCESSOR PARALLEL = 0), it should work if you have enough memory? Then, if you run your simulation in parallel model, can you check in the temporary directory if in one of the T2DCLI00007-0000X at at least one column, there is a ***** symbol rather than an integer? If yes, your problem may be solved with version 6.2 of partel.
Hope this helps,
Chi-Tuan