I've already had the case of a user whose system prevented Coollector from writing to the disk. Unfortunately, we've never been able to understand why
So we've had to use a workaround, which is to copy your coollection file to another location (for example on your desktop). Then, instead of launching the program Coollector itself, you'd double-click the coollection file from where it is.
Sorry for the trouble. I'd really like to have a better solution. But at least that solution works...