[c-nsp] Cisco 3750 refuses to reload

[Aivars]

We have a stack of 2 WS-C3750G-24T. I recently wanted to make a
software upgrade but switches refused to reload.

sw#rel
%ERROR: Not able to process Signature in flash2:.
%ERROR: Aborting reload.

I can format Flash2: or rewrite sowtware on both but it has no effect. I can
not format Flash: or Flash1:

sw#format flash:
Format operation may take a while. Continue? [confirm]
Format operation will destroy all data in "flash:".  Continue? [confirm]
%Error formatting flash (No such device)
sw#format flash1:
Format operation may take a while. Continue? [confirm]
Format operation will destroy all data in "flash1:".  Continue? [confirm]
%Error formatting flash (No such device)

I am little scared to power down the switches too as I have no
confidence of successful bootup afterwards.

Any ideas?

Aivars