Will a Rogers phone work on fido? (without unlock)?

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If you Unlock the HTC Dream from network lock only it will work on other GSM Network Sim card..Otherwise it won't work in that.You can unlock only GSM Network lock.After Unlock it use with only GSM Network Sim card...Not able to use with CDMA Network Sim card...Get the unlock code from Superunlockcodes.com and Unlock it simply.