HDD Limitation on Windows?

[TomTom]

I bought 2 1 TB Western Digital HDD last week in order to backup all the mp3 files I have. Both drives are identical 2.5 “” external drives (no own power supply but USB 3.0) from the same brand and type. Both of them work when only one of them is plugged in but as soon as I plug them both in, my OS (Windows 7 Ultimate) only assigns a drive letter to one of them. The second one is recognized (can see it under devices) but no drive letter is assigned. First I thought, it is a matter of power supply and 2x 1 TB HDD are too much but then I tried with one of the 1 TB new HDD and a 500GB older external HDD, there was no problem in assigning drive letters to both of them. So I was wondering if there is maybe a size restriction that is kicking in here. All in all I have 2 local hard drives (both 1 TB) and 2x external hard drives (also both 1 TB). Is 4 TB HDD too much for Windows or are there other reasons possible? Thanks in advance for any help with this.

[TomTom]

Re: HDD Limitation on Windows?

Problem solved..somehow Windows fucked something up on the initial plugin of the 2nd external HD. The drive showed up under volume administration as "offline" and I just switched it to "online" and boom..problem solved. So no power problem and also no 4 TB limitation.