# How to troubleshoot the GenomeStudio error "Index was outside the bounds of the array."
The GenomeStudio error "Index was outside the bounds of the array." is usually generated during project creation.
Possible causes (most common):
* GenomeStudio cannot find a data point it is looking for (e.g missing or corrupted idat).
* Manifest file selected is for the wrong Infinium beadchip type and/or version.
* Cluster file selected is for the wrong Infinium beadchip type and/or version.
Troubleshooting Steps:
* Make sure that correct manifest and/or cluster files are in use.
* In GenomeStudio, check the log file window at the bottom which may list a specific failure.
* Issue is usually not related to the sample sheet, however, for troubleshooting purposes, try creating a project without a sample sheet to exclude this possible root cause.
* Create a new project from the IDATs. If IDATs were provided by a colleague/collaborator, obtain a fresh copy of the IDATs as they may have gotten corrupted during the file transfer.
* Re-download DMAP file and re-scan the beadchips.
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