I'm curious to know if this was happening before or it started to happen lately. You may want to make sure your computer is stable, like running a disk defragmenter, scandisk, check with AntiVirus your disk and so on. You may even try to reinstall Vision Builder. Which version of NI-IMAQ and IVB do you have? Does this happens in another computer as well? When you do the sequence the progress indicator does it finishes allocating the memory before you run the acquisition?
Good luck!
Nestor.
Nestor